Journal articles: 'Soret band'

1

LASH, TIMOTHY D. "Modification of the porphyrin chromophore by ring fusion: identifying trends due to annelation of the porphyrin nucleus." Journal of Porphyrins and Phthalocyanines 05, no. 03 (March 2001): 267–88. http://dx.doi.org/10.1002/jpp.313.

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The effects exerted by fused aromatic rings on the UV-vis spectra of porphyrins are surveyed. Modified porphyrin chromophores with fused benzene, 1,2-naphthalene, 9,10-phenanthrene or phenanthroline rings are surprisingly little affected even when a maximum number of ring fusions are incorporated. Linearly annealed naphtho- or anthraporphyrins show large red shifts to the Q bands but the Soret absorptions are weakened and undergo only minor bathochromic shifts. Fluoranthoporphyrins give multiple bands in the Soret region, but the Q band region is virtually unaffected by this tetracyclic ring system. On the other hand, metal chelates of fluoranthoporphyrins show surprisingly strong bands near 600 nm. Benzothiadiazole rings split and weaken the Soret band, but the Q bands region is unexceptional. However, metal coordination again produces relatively intense bands near 600 nm. The most significant results were obtained for porphyrins with fused acenaphthylene rings. Monoacenaphthoporphyrins (41) have three Soret bands at 387, 431 and 454 nm, and the longest wavelength Q band is shifted to 658 nm. opp-Diacenaphthoporphyrin (43) further shifts these bands with two Soret absorbances at 443 and 470 nm, and an additional strong peak is observed at 692 nm. The metal complexes of these systems also show strong bands between 602 and 656 nm. Still larger effects are produced by tetraacenaphthoporphyrin (47), the dication for which in trifluoroacetic acid (TFA)–chloroform has a Soret absorption at 528 nm. Tetraaryltetraacenaphthoporphyrins (48) are even more red shifted, showing Soret bands between 556 and 570 nm for the free bases and 565 to 588 nm for the related dications. The lead(II) chelate for tetraphenylporphyrin (48a) shows an additional 'hyper' spectral shift that brings the Soret band to 604 nm, and this effect can also be achieved by introducing four meso-phenylethynyl substituents onto the tetraacenaphthoporphyrin nucleus (49). In addition, by combining these two factors for the lead(II) chelate of 49, a record-breaking value for the Soret band of 642 nm can be achieved. Spectral shifts due to ring annelation in porphyrin analogues are also discussed, including those for oxybenziporphyrins, oxypyriporphyrins, carbaporphyrins and sapphyrins.

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2

Kuroda, Kosuke, Chiaki Kodo, Kazuaki Ninomiya, and Kenji Takahashi. "A Polar Liquid Zwitterion Does Not Critically Destroy Cytochrome c at High Concentration: An Initial Comparative Study with a Polar Ionic Liquid." Australian Journal of Chemistry 72, no. 2 (2019): 139. http://dx.doi.org/10.1071/ch18533.

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A polar carboxylate-type zwitterion with a small volume of water can dissolve cytochrome c without significant disruption, compared with the case of a popular polar carboxylate-type ionic liquid, 1-ethyl-3-methylimidazolium acetate. A change in the Soret, Q, and 615nm bands was not observed in the 80 wt-% polar zwitterion solution, whereas a shift in the Soret band, diminishing Q band, and appearance of the 615nm band was found in the 80 wt-% polar ionic liquid solution. It suggests that concentrated polar ionic liquid solutions critically disrupt the structure of cytochrome c, and the polar zwitterion solution used in this study was better than a 1-ethyl-3-methylimidazolium acetate solution in a high concentration range.

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3

Franzen, Stefan, Stacie E. Wallace-Williams, and Andrew P. Shreve. "Heme Charge-Transfer Band III Is Vibronically Coupled to the Soret Band." Journal of the American Chemical Society 124, no. 24 (June 2002): 7146–55. http://dx.doi.org/10.1021/ja0172722.

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4

Kotkowiak, Michał, and Alina Dudkowiak. "Multiwavelength excitation of photosensitizers interacting with gold nanoparticles and its impact on optical properties of their hybrid mixtures." Physical Chemistry Chemical Physics 17, no. 41 (2015): 27366–72. http://dx.doi.org/10.1039/c5cp04459f.

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Different behavior of the mixtures on excitation with the wavelengths from the Soret and Q bands of the dyes and with those corresponding to the surface plasmon resonance band of gold nanoparticles, was analyzed.

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5

Brunet, Claire, Rodolphe Antoine, Jérôme Lemoine, and Philippe Dugourd. "Soret Band of the Gas-Phase Ferri-Cytochrome c." Journal of Physical Chemistry Letters 3, no. 6 (February 27, 2012): 698–702. http://dx.doi.org/10.1021/jz300070r.

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6

Raavi, Sai Santosh Kumar, Jun Yin, Giulia Grancini, Cesare Soci, Venugopal Rao Soma, Guglielmo Lanzani, and Lingamallu Giribabu. "Femtosecond to Microsecond Dynamics of Soret-Band Excited Corroles." Journal of Physical Chemistry C 119, no. 52 (December 16, 2015): 28691–700. http://dx.doi.org/10.1021/acs.jpcc.5b08235.

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7

Harmon, H. James. "Specific visible spectral changes induced by guanine binding to cytosine-derivatized porphyrin." Journal of Porphyrins and Phthalocyanines 06, no. 01 (January 2002): 73–77. http://dx.doi.org/10.1142/s1088424602000117.

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The interaction of the free nucleic acid bases adenine, cytosine, and thymidine with meso-tri(4-sulfonatophenyl) meso 4-phenyl porphyrin cytosine amide (TPSC) trisodium salt at pH 5.9, 7.4, and 9.3 results is a decrease in the absorbance of the Soret (B-band) at 413 nm of TPSC. A decrease in Soret band absorbance is observed with guanine below pH 8; at higher pH values a new absorbance band at 424 nm is observed. The appearance of the band is consistent with hydrogen bonding between the cytosine-functionalized porphyrin and guanine and the resulting perturbation of the electron orbitals of the porphyrin.

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8

Stoyanov, Stanislav R., Cindy-Xing Yin, Murray R. Gray, Jeffrey M. Stryker, Sergey Gusarov, and Andriy Kovalenko. "Density functional theory investigation of the effect of axial coordination and annelation on the absorption spectroscopy of nickel(II) and vanadyl porphyrins relevant to bitumen and crude oils." Canadian Journal of Chemistry 91, no. 9 (September 2013): 872–78. http://dx.doi.org/10.1139/cjc-2012-0532.

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The vanadium and nickel components in heavy oils and bitumen are important impurities in catalytic processing and form aggregates with other asphaltene components. Metalloporphyrins are commonly analyzed using the characteristic Soret band in the UV–vis absorption spectrum. However, the Soret band of metalloporphyrins in petroleum is broadened and weaker than expected based on the concentration of Ni and V in heavy oils and the extinction coefficients of isolated porphyrins. We hypothesize that the low intensity and broadening of the Soret band could be due to axial coordination of the metal center or fusion (annelation) of aromatic rings on the porphyrin π-system. This hypothesis is examined using the density functional theory for geometry optimization and time-dependent density functional theory (TD-DFT) for calculation of excited states of nickel(II) and vanadyl porphyrins with axially coordinated ligands and annelated polyaromatic hydrocarbons. Predictions of the excited electronic states performed using the tandem of TD-DFT and conductor-like polarizable continuum model of solvation support this hypothesis and provide insight into the extent of Soret band broadening and intensity decrease due to coordination and annelation. These computational results, validated with respect to visible absorption spectra, are important for understanding asphaltene aggregation and spectroscopic characterization and suggest methods for removal of transition metals from heavy oil.

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9

Solovyov, Konstantin N., Serguei M. Arabei, Lev L. Gladkov, Vera K. Konstantinova, Alisa E. Turkova, and Yuri S. Avlasevich. "Quasi-line vibronic spectra of 2,3,12,13-tetramethyldibenzoporphine and their interpretation." Journal of Porphyrins and Phthalocyanines 07, no. 12 (December 2003): 787–94. http://dx.doi.org/10.1142/s1088424603000975.

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The quasi-line fluorescence and fluorescence excitation spectra of 2,3,12,13-tetrame-thyldibenzoporphine have been obtained at 77 K in n-octane and analyzed. The normal-coordinate analysis of this molecule has been performed, and the spectra have been interpreted in detail. In the Soret band region the fluorescence excitation quasi-line spectra clearly reveal two 0-0 components. The problem of the nature of the Soret band of free-base porphyrins is discussed.

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10

Fujisawa, Jun-ichi. "Highly-selective absorption control in photosynthetic chlorin dyes." Journal of Porphyrins and Phthalocyanines 19, no. 04 (April 2015): 601–9. http://dx.doi.org/10.1142/s1088424614501041.

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Selective chemical control of light-absorption bands of dye molecules in which the wavelengths of two or more absorption bands are individually controlled by chemical modifications is an ultimate challenge in chemistry and an important subject for their wide applications. Recently, selective absorption tuning was first reported in photosynthetic bacteriochlorin dyes. In the bacteriochlorin dyes, either the visible or near IR band is selectively shifted by the chemical modifications almost retaining the other band. Fujisawa et al. clarified that the selective absorption tuning is accomplished by chemical control of configuration interactions in the two two-level systems. This paper reports on more highly-selective absorption tuning in photosynthetic chlorin dyes, bacteriochlorophylls (BChls) d and e and the mechanism. In BChls d and e, the near UV band (so-called Soret band) is selectively red-shifted by the chemical modifications of BChl d involving the formylation and methylation perfectly retaining the visible band (so-called Qy). Density functional theory (DFT) and time-dependent DFT analyses showed that the red-shift of the Soret band is predominantly attributed to the large stabilization of the second lowest unoccupied molecular orbital induced by the formylation. In contrast, the Qy absorption retention results from the perfect cancellation between the positive excitation-energy change due to the formylation and negative excitation-energy change due to the methylation, both of which are significantly contributed by configuration interactions. This work reveals that the highly-selective absorption control in BChls d and e is accomplished by the complicated control of configuration interactions in the four-level system.

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11

Yeh, Hsiu-Chih, Chin-Ti Chen, Jenwei Yu, Pei-Chang Tsai, and Juen-Kai Wang. "Conformation and π-conjugation of olefin-bridged acceptor on the pyrrole β-carbon of nickel tetraphenylporphyrins: implicit evidence from linear and nonlinear optical properties." Journal of Porphyrins and Phthalocyanines 11, no. 12 (December 2007): 857–73. http://dx.doi.org/10.1142/s1088424607000989.

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This paper has scrutinized, both experimentally and theoretically, the conformation of an olefinic substituent on the pyrrole β-carbon of tetraphenylporphyrin. Compelling evidences collected from linear optical absorption and NOESY 1H NMR experiment strongly suggest that, in solution, it is highly possible for the olefinic acceptor on pyrrole β-carbon to have a coplanar or near coplanar conformation with the pyrrole of the porphyrin core. This conformation ensures effective π-conjugation between the pyrrole ring and its olefinic substituent which is reflected in the linear absorption spectroscopy as the red-shifting of both Soret and Q-bands and possibly the splitting of the absorption Soret band. The intensified long wavelength absorption Q-band of the porphyrin is also consistent with the proposed π-conjugation. Regarding nonlinear optical absorption, an active nonlinear optical (NLO) response has been observed for these porphyrins, indicative of efficient electronic coupling (resonance interaction) between the electronic acceptor and porphyrin macrocyclic ring, compatible with a coplanar or near coplanar conformation in order to achieve π-conjugation. Such conformation of the peripherally appended olefinic acceptor has been further confirmed by INDO/1 Hamiltonian in the ZINDO computational calculations. The INDO/S electron density calculation further reveals that the range of intramolecular charge-transfer (ICT) does not encompass the whole porphyrin core but is mostly confined to the pyrrole ring attached to the olefin-linked acceptor. Furthermore, ICT characteristics were found to be more heavily involved in the Soret absorption band than Q-band. Our analysis of the porphyrin π-conjugation is consistent with modest solvatochromic behavior and the moderate NLO activity of the porphyrins compared with NLO chromophores with many less π-electrons.

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12

Ramadoss, C. S., B. C. Shenoy, and A. Borthakur. "Isolation and characterization of a novel haemoprotein b-559 from Bengal gram (Cicer arietinum)." Biochemical Journal 243, no. 3 (May 1, 1987): 723–28. http://dx.doi.org/10.1042/bj2430723.

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A haemoprotein was purified to apparent homogeneity from Bengal-gram seeds. The purified protein exhibited an absorption maximum at 412 nm (Soret band) that upon reduction with dithionite gave rise to a shift in the Soret band to 426 nm with concomitant appearance of an alpha-band at 559 nm and a beta-band at 530 nm. In the reduced state the Bengal-gram haemoprotein showed reactivity towards CO, nitrite and hydroxylamine. SDS/polyacrylamide-slab-gel electrophoresis showed that the haemoprotein has Mr 78,000. Gel-filtration and ultracentrifugal analyses suggest that the Bengal-gram haemoprotein is oligomeric in nature. Since it differs from photosynthetic membrane cytochrome b-559 in solubility in buffer, in reactivity towards CO and in molecular size, it appears to be a novel haemoprotein b-559.

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13

Zheng, Lifeng, Yang Meng, Xiangqian Wang, Chun Zhu, and Jin-Xia Liang. "Screening metal-dicorrole-based dyes with excellent photoelectronic properties for dye-sensitized solar cells by density functional calculations." Journal of Porphyrins and Phthalocyanines 24, no. 08 (August 2020): 1003–12. http://dx.doi.org/10.1142/s1088424620500145.

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The dye molecules behaving as photosensitizers in dye-sensitized solar cells are the most critical factors to determine the power conversion efficiency. Therefore, ways to design dye molecules with excellent photoelectric properties has been the focus of dye-sensitized solar cells research. Here, we selected four representative different metal-corrole monomers to characterize their structures and photoelectronic properties. Then based on these metal-corrole monomers, six different architectures of metal-dicorroles were designed by varying the linking forms. The most stable architecture [Formula: see text] was screened out by binding energy calculations. A further two types of metal-dicorrole-based dyes were constructed by incorporating different bridge groups with the cyanoacry acceptor into the stable metal-dicorroles. A large number of density functional theory calculations and photoelectric properties analysis indicate that among these different metal-dicorrole-based dyes, Ga-dicorrole dyes have two strong and wide absorption bands in the visible region corresponding to Soret and Q bands, respectively, and have high charge separation efficiency under optical excitation. Especially for Ga-SN dye, by incorporating a [Formula: see text]-bridge-conjugated group, its Soret absorption band is greatly enhanced, broadened and red-shifted, resulting in its merging with the Q band into one absorption band. Moreover, its charge transfer efficiency is up to 76.86%, which will facilitate its coupling with semiconductor materials and transfer its electrons to the semiconductor materials.

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14

Komatsu, Yu, Masayuki Umemura, Mitsuo Shoji, Megumi Kayanuma, Kazuhiro Yabana, and Kenji Shiraishi. "Light absorption efficiencies of photosynthetic pigments: the dependence on spectral types of central stars." International Journal of Astrobiology 14, no. 3 (December 10, 2014): 505–10. http://dx.doi.org/10.1017/s147355041400072x.

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AbstractFor detecting life from reflection spectra on extrasolar planets, trace of photosynthesis is one of the indicators. However, it is not yet clear what kind of radiation environments is acceptable for photosynthesis. Light absorption in photosystems on the Earth occurs using limited photosynthetic pigments such as chlorophylls (Chls) and bacteriochlorophylls (BChls). Efficiencies of light absorption for the pigments were evaluated by calculating the specific molecular absorption spectra at the high accuracy-quantum mechanical level. We used realistic stellar radiation spectra such as F, G, K and M-type stars to investigate the efficiencies. We found that the efficiencies are increased with the temperature of stars, from M to F star. Photosynthetic pigments have two types of absorption bands, the Qy and Soret. In higher temperature stars like F star, contributions from the Soret region of the pigments are dominant for the efficiency. On the other hand, in lower temperature stars like M stars, the Qy band is crucial. Therefore, differences on the absorption intensity and the wavelength between the Qy and Soret band are the most important to characterize the photosynthetic pigments. Among photosynthetic pigments, Chls tend to be efficient in higher temperature stars, while BChls are efficient for M stars. Blueward of the 4000 Å break, the efficiencies of BChls are smaller than Chls in the higher temperature stars.

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15

de Miguel, Gustavo, Kohei Hosomizu, Tomokazu Umeyama, Yoshihiro Matano, Hiroshi Imahori, María T. Martín-Romero, and Luis Camacho. "Tunable Soret-Band Splitting of an Amphiphilic Porphyrin by Surface Pressure." ChemPhysChem 9, no. 11 (August 4, 2008): 1511–13. http://dx.doi.org/10.1002/cphc.200800270.

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16

Fonseka, Priyani V., Gayathri Vasudevan, Lisa-Jo Ann Clarizia, and Melisenda J. McDonald. "Temperature Dependent Soret Spectral Band Shifts Accompany Human CN-Mesohemoglobin Assembly." Protein Journal 26, no. 4 (December 27, 2006): 257–63. http://dx.doi.org/10.1007/s10930-006-9067-7.

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17

Uoyama, Hiroki, Takahiro Takiue, Kazuyuki Tominaga, Noboru Ono, and Hidemitsu Uno. "Synthesis, structures, and properties of BCOD-fused porphyrins and benzoporphyrins." Journal of Porphyrins and Phthalocyanines 13, no. 01 (January 2009): 122–35. http://dx.doi.org/10.1142/s108842460900022x.

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Bicyclo[2.2.2]octadiene (BCOD)-fused porphyrins with no other substituents were prepared by [2 + 2] and [3 + 1] porphyrin syntheses from ethanodihydroisoindole derivatives in fairly good yields. Thermal retro-Diels-Alder reactions of BCOD-fused porphyrins gave the corresponding benzoporphyrins with no substituent in quantitative yields. Their UV-vis spectra and crystal structures were carefully examined in terms of π-system expansion of the porphyrin ring current. In the cases of monobenzo- and adj-dibenzo-porphyrins, a single Soret band in their UV-vis spectra and no bond alteration in the benzene rings of their crystal structures were observed, while the split Soret bands and the obvious bond alteration in their benzene rings were recorded in the case of opp-dibenzoporphyrin.

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18

Liu, Li Li, Yun Fang Zhao, and Wei Jun Jin. "Investigation on the effect of water on the spectroscopic behaviors of TPPS in acidic imidazolium-based ionic liquids." Journal of Porphyrins and Phthalocyanines 16, no. 10 (October 2012): 1132–39. http://dx.doi.org/10.1142/s1088424612501118.

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The effect of water on the spectroscopic behaviors of meso-tetrakis-(4-sulfonatophenyl) porphyrin (TPPS) in acidic 1-butyl-3-methylimidazolium tetrafluoroborate (BMIMBF4) and 1-ethyl-3-methylimidazolium tetrafluoroborate (EMIMBF4) is investigated by spectroscopic methods. In acidic ionic liquids without water, the Soret bands of the protonated form (H4TPPS2-) and J-aggregates of TPPS are centered at 449 and 469 nm, respectively, and the Q-band is centered at 679 nm. When increasing the content of water, the Soret band of H4TPPS2- is blue-shifted to 430 nm. However, the Soret and Q-bands of J-aggregates are red-shifted to 487 and 701 nm, respectively. The NMR and pyrene-scale polarity experiments reveal that the change of the bulk environment is responsible for the red-shift of J-aggregates and the blue-shift of H4TPPS2-. According to the analysis of the fluorescence spectra, the content of H4TPPS2- increases gradually with the addition of water, while the content of H2TPPS4- takes the opposite trend. Simultaneously, the content of J-aggregates decreases substantially when the addition of water is 0 ~ ca. 12 μL (or 13 μL) but it decreases slowly with further addition of water. Remarkably, the fluorescence intensity of J-aggregates is relatively strong. In addition, the fluorescence of J-aggregates can be detected when λex is set at both λex for TPPS monomers and λex for J-aggregates. While the fluorescence of TPPS monomers can be detected only when λex is set at λex for monomers. Moreover, with the addition of water, the fluorescence lifetimes of H2TPPS4- and H4TPPS2- increase from 3.202 and 0.830 ns to 9.623 and 2.964 ns, respectively.

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19

MAHAJAN, AMAN, ANSHUL KUMAR, MANDEEP SINGH, DINESH PATHAK, and R. K. BEDI. "CHARACTERIZATION OF DROP CASTED CuTsPc FILMS ON ITO SUBSTRATES." International Journal of Nanoscience 12, no. 01 (February 2013): 1350001. http://dx.doi.org/10.1142/s0219581x13500014.

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This study evaluated the possibility of utilizing a drop-cast process for CuTsPc -based organic solar cells. CuTsPc thin films were deposited by drop-cast method on ITO substrate. The absorption spectra of these films show two well-defined absorption bands of phthalocyanine molecule, namely, the soret (B) and Q-band. The band gaps calculated from the absorption spectra is found to lie in the range of 1.55–4.04 eV. X-ray diffractogram of the films indicate their polycrystalline nature. Atomic force microscope (AFM) investigations of the films show granular grain like morphology. The data for mobility, dielectric constant, extinction coefficient and refractive index are also presented in this communication.

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20

Furuyama, Taniyuki, Takuya Yoshida, Daisuke Hashizume, and Nagao Kobayashi. "Phosphorus(v) tetraazaporphyrins: porphyrinoids showing an exceptionally strong CT band between the Soret and Q bands." Chem. Sci. 5, no. 6 (2014): 2466–74. http://dx.doi.org/10.1039/c4sc00569d.

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21

Bernardini, Martina Shasa, Juhee Kim, Hyeokjun Kim, Minkyu Song, Woo-Dong Jang, Dae Sung Chung, and In Hwan Jung. "Wavelength-selective porphyrin photodiodes via control of Soret- and Q-band absorption." Dyes and Pigments 193 (September 2021): 109531. http://dx.doi.org/10.1016/j.dyepig.2021.109531.

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22

Yakavets, Ilya, Igor Yankovsky, Lina Bezdetnaya, and Vladimir Zorin. "Soret band shape indicates mTHPC distribution between β-cyclodextrins and serum proteins." Dyes and Pigments 137 (February 2017): 299–306. http://dx.doi.org/10.1016/j.dyepig.2016.11.007.

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23

Götze, Jan P., Dominik Kröner, Shiladitya Banerjee, Bora Karasulu, and Walter Thiel. "Carotenoids as a Shortcut for Chlorophyll Soret-to-Q Band Energy Flow." ChemPhysChem 15, no. 15 (September 1, 2014): 3392–401. http://dx.doi.org/10.1002/cphc.201402233.

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24

Yu, Chuan Ming, and Bing Cheng Hu. "Synthesis and Fluorescence Study of Cobalt(II) Deuteroporphyrin Dimethyl Ester." Advanced Materials Research 989-994 (July 2014): 694–96. http://dx.doi.org/10.4028/www.scientific.net/amr.989-994.694.

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A series of metal-DPDME (metal deuteroporphyrin dimethyl ester) complex were synthesized through dehydrogenation, deferrization, esterification, metal-complexation using hemin as raw materials. Found red shift at Soret band and blue shift at Q band in UV-Vis spectrum which is different from tetraphenylporphyrin, and different excitation and emission peaks in fluorescence spectrum between DPDME and Co (II)-DPDME.

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Bondarenko, V. M., Yu V. Alexeev, O. V. Mislavsky, and G. V. Ponomarev. "Perspectives of disodium salt 2.4-di(1-metoxyethyl)-deuteroporphyrin – IX (“dimegin”) application for photodynamic therapy in non-oncologic cases." Biomeditsinskaya Khimiya 60, no. 3 (2014): 338–47. http://dx.doi.org/10.18097/pbmc20146003338.

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Effects of disodium salt 2,4-di(1-metoxyethyl)-deuteroporphyrine-IX (Dimegin) and the light from Soret band (»395-405 nm) at the viability of microbial cells and at their potential to form microbial biofilms have been compared with traditional antiseptics. Irradiation of microbial cells of S. aureus, E. coli, C. albicans and others with diode light (power density 0.05 Wt/cm2) caused a bactericidial effect similar to that obtained with standard anticeptics (chlorhexidine and dioxidine). A comparative study of the effectiveness of Dimegin and Photoditazine (a soluble salt of chlorine e6) as photosensitizers have been performed using the test system of erythrocyte hemolysis in vitro under irradiation with light from the Sore band. Results have shown insignificant difference in the photodynamic effect with similar doses of absorbed light and preparation concentration.

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Qian, Dong-Jin, Chikashi Nakamura, Tatsuki Wakayama, and Jun Miyake. "Synthesis and multilayer assembly of multiporphyrin arrays at the water-chloroform interface." Journal of Porphyrins and Phthalocyanines 07, no. 06 (June 2003): 415–19. http://dx.doi.org/10.1142/s1088424603000537.

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A water-chloroform interface was developed for the synthesis and assembly of the cadmium-mediated multiporphyrin arrays. With the use of a vertical dipping method, multilayers of the multiporphyrin can be deposited onto hydrophobic substrate surfaces. An in situ absorbance measurement at the water-porphyrin chloroform interface revealed a blue shift for the porphyrin Soret band after the addition of CdCl 2 into the water phase. The transferred multilayers showed a broad Soret band from 430 to 442 nm, which is ascribed to monomer-like porphyrin arrangement in the planar layer and aggregates in the interlayer. The orientation angle of porphyrin macrocycles is about 30°. The porphyrin emission properties in the present multilayers are compared to those in the monomer and aggregate prepared from the air-water/ CdCl 2 subphase surfaces.

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27

MACK, JOHN, and MARTIN J. STILLMAN. "Assignment of the optical spectrum of metal porphyrin and phthalocyanine radical anions." Journal of Porphyrins and Phthalocyanines 05, no. 01 (January 2001): 67–76. http://dx.doi.org/10.1002/1099-1409(200101)5:1<67::aid-jpp300>3.0.co;2-3.

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The approach developed previously to assign the major π → π* and π* → π* bands in the optical spectra of metallophthalocyanine radical species [ MPc (−n)](n−2)− (n = 1–6), which was based on spectral band deconvolution analyses of the UV-vis absorption and magnetic circular dichroism (MCD) spectra and ZINDO calculations, is reviewed in this paper and extended to the major bands observed in the spectrum of the zinc tetraphenylporphyrin radical anion [ ZnTPP (−3)]−. The magnetic circular dichroism spectrum is dominated by an intense pseudo A term associated with the B (or Soret) transition with bands at 445 and 465 nm. Weaker bands associated with the π* → π* transition out of the partially filled LUMO give rise to two widely separated, oppositely signed, coupled B terms in the MCD spectrum at 538 and 910 nm. The Q transition is assigned to a weak absorption band at 750 nm and a shoulder slightly to the blue at 728 nm.

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Torres-Garcia, Alicia Elena, Jose M. Perez-Escudero, Inigo Ederra, and Ramon Gonzalo. "Modified Soret Lenses for Dual-Band Integrated Detectors at Millimetre and Submillimetre Wavelengths." IEEE Transactions on Terahertz Science and Technology 10, no. 2 (March 2020): 107–17. http://dx.doi.org/10.1109/tthz.2019.2957476.

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29

Móger, G. "Solvent effect on the dissociation constants and Soret band maxima of hematoporphyrin diacid." Reaction Kinetics & Catalysis Letters 54, no. 2 (February 1995): 329–36. http://dx.doi.org/10.1007/bf02071027.

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30

Vacha, Martin, Shinjiro Machida, and Kazuyuki Horie. "Spectral hold burning in the Soret absorption band of a zinc tetrabenzoporphin derivative." Chemical Physics Letters 242, no. 1-2 (August 1995): 169–76. http://dx.doi.org/10.1016/0009-2614(95)00725-j.

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31

Kubota, T., and S. Yoshikawa. "Hydrazine and hydroxylamine as probes for O2-reduction site of mitochondrial cytochrome c oxidase." Biochemical Journal 292, no. 2 (June 1, 1993): 519–24. http://dx.doi.org/10.1042/bj2920519.

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Reactions of hydrazine and hydroxylamine with bovine heart cytochrome c oxidase in the fully reduced state were investigated under anaerobic conditions following the visible-Soret spectral change. Hydrazine gave a sharp band at 575 nm with 20% decrease in the alpha band at 603 nm, and hydroxylamine induced a 2 nm blue-shift for the alpha band without any clear splitting. The Soret band at 443 nm was decreased significantly in intensity, with the concomitant appearance of a shoulder with hydrazine or a peak with hydroxylamine, both near 430 nm. The dependence on pH of the affinity of these reagents for the enzyme indicates that only the deprotonated forms of these reagents bind to the enzyme, suggesting a highly hydrophobic environment of the haem ligand-biding site. These spectral changes were largely removed by addition of cyanide or CO. However, detailed analysis of these spectral changes indicates that hydrazine perturbs the shape of the spectral change induced by cyanide and hydroxylamine perturbs that induced by CO. These results suggest that these aldehyde reagents bind to haem a3 iron as well as to a second site which is most likely to be the formyl group on the haem periphery, and that these two sites bind these reagents anti-cooperatively with each other.

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32

Nevonen, Dustin E., Elena A. Makarova, Alexander King, Evgeny A. Lukyanets, and Victor N. Nemykin. "Elucidation of the electronic structure of water-soluble quaternized meso-tetrakis(3-pyridyl)bacteriochlorin derivatives by experimental and theoretical methods." Journal of Porphyrins and Phthalocyanines 22, no. 11 (October 18, 2018): 965–71. http://dx.doi.org/10.1142/s1088424618500980.

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Three water-soluble quaternized metal-free tetra-(3-pyridyl)bacteriochlorins were synthesized and characterized by UV-vis, MCD, and NMR spectroscopy as well as elemental analysis. DFT calculations are indicative of the [Formula: see text]HOMO [Formula: see text] [Formula: see text]LUMO relationship, which correlates well with the experimentally observed by MCD spectroscopy for all bacteriochlorins “reversed” sign sequence in the Vis-NIR region. TDDFT calculations also correctly predict large splitting between the [Formula: see text] and [Formula: see text] bands as well as splitting of the Soret band observed experimentally in all bacteriochlorins.

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33

Ogata, Hiroshi, Ryuji Higashi, and Nagao Kobayashi. "Electronic absorption spectra of substituted phthalocyanines in solution and as films." Journal of Porphyrins and Phthalocyanines 07, no. 08 (August 2003): 551–57. http://dx.doi.org/10.1142/s1088424603000690.

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The electronic absorption spectra of several phthalocyanines substituted at the so-called α-, β- and α and β-positions of the macrocycle have been recorded in solution and as films (α = 1,4,8,11,15,18,22, and 25 positions or 1,8 (or 11),15 (or 18), and 22 (or 25) positions, and β = 2,3,9,10,16,17,23, and 24 positions or 2,9 (or 10),16 (or 17), and 23 (or 24) positions). Phthalocyanines substituted with bulky groups at the α-positions prevent cofacial aggregation so that their Q-absorption band remains at a similar wavelength both in solution and films, although the film spectra are generally broader. Phthalocyanines substituted at the β-positions are apt to aggregate cofacially in polar solvents but in films they may show broad Q-bands which spread out to both shorter and longer wavelengths of the solution Q-band, depending on the bulkiness of the substituents. The film spectra of hexadeca-substituted phthalocyanines exhibit Q-bands at a similar wavelength as in solution, with insignificant broadening of the Q-band on film formation. However, the Soret bands for most of the substituted phthalocyanines are shifted and broadened to longer wavelength in the films.

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34

Imahori, Hiroshi. "Porphyrins as Potential Sensitizers for Dye-Sensitized Solar Cells." Key Engineering Materials 451 (November 2010): 29–40. http://dx.doi.org/10.4028/www.scientific.net/kem.451.29.

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Recently, dye-sensitized solar cells have attracted much attention relevant to global environmental issues. So far ruthenium(II) bipyridyl complexes have proven to be the most efficient TiO2 sensitizers in dye-sensitized solar cells. However, the highest power conversion efficiency has been stagnated in recent years. More importantly, considering that ruthenium is rare and expensive, novel dyes without metal or using inexpensive metal are desirable for highly efficient dye-sensitized solar cells. To fulfill the requirement, it is crucial to develop inexpensive novel dyes that exhibit high efficiencies in terms of light-harvesting, charge separation, and charge collection. Porphyrins are important classes of potential sensitizers for highly efficient dye-sensitized solar cells owing to their photostability and potentially high light-harvesting capabilities that would allow applications in thinner, low-cost dye-sensitized solar cells. However, typical porphyrins possess an intense Soret band at 400 nm and moderate Q bands at 600 nm, which does not match solar energy distribution on the earth. Therefore, the unmatched light-harvesting property relative to the ruthenium complexes has limited the cell performance of porphyrin-sensitized TiO2 cells. Elongation of the -conjugation and loss of symmetry in porphyrins cause broadening and red-shift of the absorption bands together with an increasing intensity of the Q bands relative to that of the Soret band. On the basis of the strategy, the cell performance of porphyrin-sensitized solar cells has been improved remarkably by the enhanced light absorption. The efficiency of porphyrin-sensitized solar cells could be improved significantly if the dyes with larger red and near-infrared absorption could be developed.

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35

Akbar, Ari Yustisia, and Tania Avianda Gusman. "Synthesis and Photoluminescence Properties of Alkylbromoporphyrin." JKPK (Jurnal Kimia dan Pendidikan Kimia) 6, no. 3 (December 31, 2021): 384. http://dx.doi.org/10.20961/jkpk.v6i3.56927.

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The usage of porphyrin as a light-harvesting chromophore is considered as one of the keys to obtaining low-cost and high-efficiency dye-sensitized solar cell (DSSC). In this paper, a novel porphyrin, 5,10,15-tris(nitrophenyl)-20-(p-(11-bromo)dodecoxyphenyl))porphyrin, having a long alkyl chain and three nitro groups was synthesized. The nitro groups serve as anchoring groups to TiO2 surfaces and long alkyl chain prevents unwanted dye aggregation. The porphyrin was synthesized by condensation of p-(12-Bromododecoxy)benzaldehyde and pyrrole in propionic acid according to an adaptation of the general Rothemund method <a href="https://doi.org/10.1021/ja01265a096">[1]</a>. p-(12-Bromododecoxy)benzaldehyde was synthesized by nucleophilic substitution reaction between 4-hydroxybenzaldehyde and 1,12-dibromododecane in acetone. The reaction products were analyzed by 1H-NMR and mass spectroscopy. The absorption and fluorescence spectra of the porphyrin were also recorded. As results, the absorption spectrum of the porphyrin consists of a strong Soret and four weak Q-band. Compared to 5,10,15-tris(nitrophenyl)-20-(p-(11-bromo)dodecoxyphenyl))porphyrin spectrum, there is no wavelength shifting because of the incorporation of the alkyl chain. The fluorescence spectrum of the porphyrin shows two characteristic emission bands and the intensity ratio of those emission bands is always constant when irradiated by different excitation wavelength related to Soret and Q-band.

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36

Arunkumar, Chellaiah, Fasalu Rahman Kooriyaden, and Subramaniam Sujatha. "Structural, spectroscopic and electrochemical investigations on fluorinated meso-tetraaryl porphyrins." Journal of Porphyrins and Phthalocyanines 21, no. 09 (September 2017): 622–31. http://dx.doi.org/10.1142/s108842461750064x.

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Two series of meso-phenyl fluorinated porphyrins and their metal complexes, 5,10,15,20-tetrakis(2[Formula: see text],4[Formula: see text],6[Formula: see text]-trifluorophenyl)porphyrin, MT(2[Formula: see text],4[Formula: see text],6[Formula: see text]-TFP)Ps (2a–2d) and 5,10,15,20-tetrakis[3[Formula: see text],5[Formula: see text]-bis(trifluoromethylphenyl)]porphyrin, MT(3[Formula: see text],5[Formula: see text]-BTFMP)Ps (3a–3d); where M [Formula: see text] 2H; Ni(II); Cu(II) and Zn(II) have been synthesized and characterized using various spectroscopic techniques including UV-visible, fluorescence and [Formula: see text]H NMR and mass spectrometry. Electronic absorption spectra of porphyrins show the typical Soret (B) and visible (Q) bands. Free ligands and zinc(II) derivatives display two well-defined emission bands around 600–660 nm and 650–720 nm upon exciting the Soret band. Porphyrins, 1d, 2a, 2b, 2c, 3a and 3d were structurally characterized by single crystal XRD analysis, and various intermolecular interactions present in them were quantified on the basis of Hirshfeld surfaces and 2D fingerprint plots. Electrochemical studies were performed and the HOMO–LUMO energy gap is high for all the porphyrins compared to MTPPs.

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Gangemi, Chiara M. A., Rosalba Randazzo, Massimiliano Gaeta, Cosimo G. Fortuna, Maria E. Fragalà, Roberto Purrello, and Alessandro D’Urso. "Synthesis and characterization of 5-(4-carboxyphenylspermine)-10,15,20-triphenylporphyrin." Journal of Porphyrins and Phthalocyanines 24, no. 05n07 (May 2020): 802–8. http://dx.doi.org/10.1142/s1088424619501839.

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We synthetized and characterized a mono spermine porphyrin derivative by NMR, UV-vis and fluorescence spectroscopy. The photophysical properties and the protonation equilibria of 5-(4-carboxyphenylspermine)-10,15,20-triphenylporphyrin have been investigated, showing that porphyrin does not aggregate in acidic solutions, differently from what occurs as soon as the core of the porphyrin is deprotonated. These aggregation processes have been detected by the rising of new fluorescence band and a significant splitting of the Soret band.

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38

Bolgiano, B., I. Salmon, W. J. Ingledew, and R. K. Poole. "Redox analysis of the cytochrome o-type quinol oxidase complex of Escherichia coli reveals three redox components." Biochemical Journal 274, no. 3 (March 15, 1991): 723–30. http://dx.doi.org/10.1042/bj2740723.

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Potentiometric analyses of the cytochrome o-type oxidase of Escherichia coli, using membranes from a strain containing amplified levels of the cytochrome bo complex, were conducted to resolve the redox centres of the oxidase. The cytochrome o-type oxidase of E. coli, a quinol oxidase, contains 2 mol of b-type haem per mol of complex and copper. Detailed analysis of potentiometric titrations, based on the absorbance of the Soret band, suggests that there are three contributions with midpoint potentials (Em,7) around +55 mV, +211 mV and +408 mV, all with maxima at 426-430 nm in the reduced state. In the alpha region of the spectra, a component with Em,6.85 = +58 mV has a maximal peak at 557 nm, and twin peaks at 556 and 564 nm nitrate with Em,6.85 = +227 mV. A feature corresponding to the highest potential Soret contribution was not observed. These data can be explained either by a model incorporating haem-haem interaction or by attributing the shorter-wavelength band (557 nm) to haem b and a split alpha-band (556, 564 nm) to the haem o (oxygen-binding haem b). Absolute spectra of oxidized membranes show continuous absorbance from 460 to 530 nm and suggest the presence of a high-spin haem component in the membranes. Monitoring absorbance at 635 minus 672 nm, contributions with midpoints (Em,7) around +52 mV, +234 mV and +371 mV are observed. This latter contribution is possibly the highest-potential component which titrates with Em greater than +400 mV in the Soret region and may represent copper-haem coupling in the cytochrome o complex.

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39

Yan, Jia Ying, Ya Qing Feng, Fang Qun Zhou, Yi Wen Chang, and Bao Zhang. "Studies on Sonogashira Coupling Reaction of Dibenzoporphyrin." Advanced Materials Research 581-582 (October 2012): 317–21. http://dx.doi.org/10.4028/www.scientific.net/amr.581-582.317.

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Changing the proportion of NBS and porphyrin, dibromination of β, β’- π-extended porphyrins was found to selectively occur to the β and β’ position of the porphyrins which is antipotal to the fused aromatic ring. Subsequent Sonogashira coupling of the resultant dibromoporphyrin introduced a carboxylphenylethynyl group to the π-extended porphyrin and the π conjugation was thus further elongated. The coupling products have shown a broadening and a red-shift of the Soret band and Q bands in the UV-Vis absorption spectra compared with the π-extended porphyrin starting materials and the original unmodified porphyrins.

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40

Prasad, Rajendra, and Ajay Kumar. "Synthesis, spectroscopic and electrochemical investigations of supramolecular nickel(II)tetraazaporphyrin complexes." Journal of Porphyrins and Phthalocyanines 09, no. 07 (July 2005): 509–18. http://dx.doi.org/10.1142/s1088424605000629.

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The ( bpy )2 Ru II and ( phen )2 Ru II moieties were linked to [ Ni ( OBTTAP )]1, periphery through coordinate bonds in order to synthesize cationic di- and pentanuclear complexes 2-5 that were obtained as PF 6− salts. They were characterized by IR, 1 H NMR, UV-vis, and mass spectral data. The electronic absorption, emission and redox data of these bichromophoric systems indicate the presence of a high degree of intercomponent electronic interaction. The position and relative intensities of the Soret and Q bands in these complexes is altered due to peripheral binding of the metal units. The compounds were non-emissive for the Q band excitation but, Soret excitation led to a strong S 2 emission, observed between 400-450 nm. In cyclic voltammetry, the compounds exhibited one Ru centered oxidation together with one or two OBTTAP centered oxidations. The Ru II/ Ru III oxidations were observed at significantly lower potentials as compared to the corresponding simple maleonitrile-benzylthioether complexes and has been interpretted in terms of weaker d π( S )– d π( Ru ) interactions.

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41

Arcot, Lokanathan, Srinivasan Kandaswamy, Anil Modali, and Tathagato Rai Dastidar. "Hemoglobin estimation using ultra-low path length in microfluidic chips by quantifying Soret band." AIP Advances 11, no. 7 (July 1, 2021): 075323. http://dx.doi.org/10.1063/5.0057490.

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42

RICH, PETER R., and THOMAS E. WIGGINS. "Soret and visible band circular dichroism measurements on the cytochrome bc1 and bf complexes." Biochemical Society Transactions 20, no. 3 (August 1, 1992): 241S. http://dx.doi.org/10.1042/bst020241s.

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43

Koch, Federico, Martin Kullmann, Ulrike Selig, Patrick Nuernberger, Daniel C. G. Götz, Gerhard Bringmann, and Tobias Brixner. "Coherent two-dimensional electronic spectroscopy in the Soret band of a chiral porphyrin dimer." New Journal of Physics 15, no. 2 (February 5, 2013): 025006. http://dx.doi.org/10.1088/1367-2630/15/2/025006.

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44

Ye, Shuji, and Andrea Markelz. "Hydration Effects on Energy Relaxation of Ferric Cytochrome C Films after Soret-Band Photoexcitation." Journal of Physical Chemistry B 114, no. 46 (November 25, 2010): 15151–57. http://dx.doi.org/10.1021/jp104217j.

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45

Cox, Dennis D., Sung K. Chang, M. Yusoff Dawood, Gregg Staerkel, Urs Utzinger, Rebecca R. Richards-Kortum, and Michele Follen. "Detecting the Signal of the Menstrual Cycle in Fluorescence Spectroscopy of the Cervix." Applied Spectroscopy 57, no. 1 (January 2003): 67–72. http://dx.doi.org/10.1366/000370203321165223.

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Fluorescence spectroscopy of the cervix has been shown to be an effective noninvasive diagnostic tool for cervical intraepithelial neoplasia (precancer). To assess the effect of the menstrual cycle on fluorescence spectroscopy, daily measurements were made on ten subjects for the length of their cycle. These measurements were analyzed to determine if there was a statistically significant signal associated with the menstrual cycle. A signal was found for emission wavelengths between 425 and 445 nm inclusive—near the main hemoglobin absorption band, the Soret band, at 420 nm. We suspect that the slight displacement of the Soret band is due to the nearby dominant NAD(P)H peak, which increases the signal-to-noise ratio and affects statistical significance. The signal consists of a reduction in fluorescence intensity for the first few days of the cycle. This analysis indicates that hemoglobin absorption is the main menstrual-cycle effect on the use of fluorescence spectroscopy on the cervix. The effect is confined to a small set of excitation/emission wavelengths and to approximately the first 8 days of the cycle. This suggests that any problems from the menstrual cycle can be avoided with a simple requirement that the device not be used during the period of menstrual bleeding.

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46

Gebicka, Lidia, and Joanna Didik. "Mechanism of peroxynitrite interaction with cytochrome c." Acta Biochimica Polonica 50, no. 3 (September 30, 2003): 815–23. http://dx.doi.org/10.18388/abp.2003_3673.

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Kinetics of the reaction of peroxynitrite with ferric cytochrome c in the absence and presence of bicarbonate was studied. It was found that the heme iron in ferric cytochrome c does not react directly with peroxynitrite. The rates of the absorbance changes in the Soret region of cytochrome c spectrum caused by peroxynitrite or peroxynitrite/bicarbonate were the same as the rate of spontaneous isomerization of peroxynitrite or as the rate of the reaction of peroxynitrite with bicarbonate, respectively. This means that intermediate products of peroxynitrite decomposition, (.)OH/(.)NO(2) or, in the presence of bicarbonate, CO(3)(-)(.)/(.)NO(2), are the species responsible for the absorbance changes in the Soret band of cytochrome c. Modifications of the heme center of cytochrome c by radiolytically produced radicals, (.)OH, (.)NO(2) or CO(3)(-)(.), were also studied. The absorbance changes in the Soret band caused by radiolytically produced (.)OH or CO(3)(-)(.) were much more significant that those observed after peroxynitrite treatment, compared under similar concentrations of radicals. (.)NO(2) produced radiolytically did not interact with the heme center of cytochrome c. Cytochrome c exhibited an increased peroxidase-like activity after reaction with peroxynitrite as well as with radiolytically produced (.)OH, (.)NO(2) or CO(3)(-)(.) radicals. This means that modification of protein structure: oxidation of amino acids and/or tyrosine nitration, facilitates reaction of H(2)O(2) with the heme iron of cytochrome c, followed by reaction with the second substrate.

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47

DiFeo, T. J., and A. W. Addison. "Haem-binding-site heterogeneity and haem Cotton effects of Glycera dibranchiata monomeric haemoglobins." Biochemical Journal 260, no. 3 (June 15, 1989): 863–71. http://dx.doi.org/10.1042/bj2600863.

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The five major components of the monomeric haemoglobin from Glycera dibranchiata were separated and characterized by absorption spectroscopy, isoelectric focusing, azide-binding affinities and nitrosyl autoreduction kinetics. The differences found among the components are discussed in terms of haem-pocket variations. In addition, the Fourier-transform i.r. spectra of pooled monomeric haemoglobin carbonyl (HbmCO) and the major component carbonyl are reported. The c.d. spectra of the carbonyl and azide derivatives of the five components are compared and found to be similar. The c.d. spectra of myoglobin(II) carbonyl [Mb(II)CO] and of apomyoglobin (apoMb) reconstituted with a symmetric synthetic iron porphyrin carbonyl, meso-tetra-(p-carboxyphenyl)porphinatoiron(II) carbonyl [TCPPFe(II)CO], are compared with the c.d. spectra of pooled HbmCO and its TCPPFe(II)CO analogue. HbmTCPPFe(II)CO shows a negative Soret c.d. band whereas MbTCPPFe(II)CO produces both a negative and a positive Soret c.d. band. Displacement of the symmetric porphyrin by 8-anilinonaphthalene-1-sulphonate and the resulting fluorescence emission are reported.

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48

EL-NAHASS, M. M., K. F. ABD-EL-RAHMAN, A. A. M. FARAG, and A. A. A. DARWISH. "OPTICAL CHARACTERISATION OF THERMALLY EVAPORATED NICKEL PHTHALOCYANINE THIN FILMS." International Journal of Modern Physics B 18, no. 03 (January 30, 2004): 421–34. http://dx.doi.org/10.1142/s0217979204023982.

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Optical properties of thermally evaporated nickel phthalocyanine thin films have been characterised using spectrophotometric measurements of transmittance and reflectance in spectral range 200–2100 nm. The refractive index n and the absorption index k were calculated. Some of the optical absorption parameters, namely optical absorption coefficient (α), molar extinction coefficient (ε molar ), oscillator strength (f), electric dipole strength (q2) and absorption half bandwidth (Δλ) of the principal optical transitions have been also evaluated. The analysis of the spectral behaviour of the absorption coefficient (α), in the absorption region revealed indirect transitions. The fundamental and the onset energy gaps were estimated as 2.77±0.02 eV and 1.58±0.01 eV, respectively. According to the analysis of dispersion curves, the dielectric constants and dispersion parameters were obtained. The absorption measurements recorded in the UV–VIS region show two well defined absorption bands of phthalocyanine molecule, namely the Soret band (B) and the Q band. The Q band shows its characteristic splitting (Davydov splitting), and ΔQ was obtained as 0.21 eV. Discussion of the obtained results and their comparison with the previous published data are also given.

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49

Qi, Ming-Hui, and Guo-Fa Liu. "Synthesis, electrochemical, photovoltaic, and photo-physical properties on the lanthanide(III) complexes of acetylacetonate and meso-tetraalkyltetrabenzoporphyrin with electric-field induction." Journal of Porphyrins and Phthalocyanines 08, no. 10 (October 2004): 1187–95. http://dx.doi.org/10.1142/s1088424604000520.

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Lanthanide(III) complexes with acetylacetonate and meso-tetraalkyltetrabenzoporphyrin (TATBP) having the general formula Ln ( TATBP )acac (where Ln = Tb , Dy , Ho , Er , Tm , Yb ; A = C 12 H 25; Hacac = acetylacetone) are reported. These compexes have been studied by elemental analyses, ultraviolet visible spectra, infrared spectra, molar conductance, 1 H NMR spectra, cyclic voltammetry, surface photovoltage spectroscopy (SPS), and luminescence spectroscopy. The infrared spectral bands of the ligand and complexes were assigned. In dimethylformamide (DMF), 0.1 M tetrabutylammonium perchlorate (TBAP), the synthesized TATBP exhibit two one-electron reversible redox reactions, and Ln(TATBP)acac shows three redox reactions respectively, within the accessible potential window of the solvent. The absorption bands of the complexes appear in the range 431-433 (Soret band), 578-580 (Q band) and 627-631 (Q band) nm. The photovoltaic properties and charge transfer process of these compounds were investigated by surface photovoltage spectroscopy (SPS) and electric-field-induced surface photovoltage spectroscopy (EFISPS) techniques, which reveal that the ligand TATBP and the complexes Er(TATBP)acac are p-type semiconductors. The spectral bands of TATBP correspond to π → π* transitions. Quantum yields of the S 1 → S 0 fluorescence are in the region 0.25-0.27 and the fluorescence lifetimes are in the region 0.014-0.022 ms at room temperature. The phosphorescence bands of the complex at 77 K appears 714 nm.

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50

Sorasaenee, Karn, Pouyan Taqavi, Lawrence M. Henling, Harry B. Gray, Elena Tkachenko, Atif Mahammed, and Zeev Gross. "Amphiphilic aluminium(III) and gallium(III) corroles." Journal of Porphyrins and Phthalocyanines 11, no. 03 (March 2007): 189–97. http://dx.doi.org/10.1142/s1088424607000242.

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The preparation and spectroscopic properties of a series of metallocorroles with polar head groups CHO and CH = C ( CN )( COOH ) are reported, as well as the X-ray crystal structure of 5,10,15-tris(pentafluorophenyl)corrolatoaluminium(III)bispyridine (triclinic space group (P-1) with unit cell parameters: a = 9.426(1) Å; b = 13.202(1) Å; c = 19.936(1) Å; α = 74.19(1)°; β = 78.47(1)°; γ = 75.75(1)°; V = 2289.57(8) Å3). Amphiphilic aluminium(III) and gallium(III) corroles exhibit electronic absorption (Soret peaks between 410 and 448 nm; Q-bands between 584 and 638 nm) and fluorescence (band maxima between 634 and 706 nm) at lower energies than their hydrophobic analogs.

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Journal articles on the topic 'Soret band'

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