Relevant bibliographies by topics / Defects Chemistry

Academic literature on the topic 'Defects Chemistry'

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Published: 7 July 2024
Last updated: 7 July 2024

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Contents

  1. Journal articles
  2. Dissertations / Theses
  3. Books
  4. Book chapters
  5. Conference papers
  6. Reports

Journal articles on the topic "Defects Chemistry":

1

Gabániová, Mária. "Surface Chemistry-Based Surface Defects Situated on Steel Strips Edges." Defect and Diffusion Forum 405 (November 2020): 199–204. http://dx.doi.org/10.4028/www.scientific.net/ddf.405.199.

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Two thirds of all examined defect cases present on rolled steel strips appeared to be chemical in nature. They are characterized by a modification in surface chemistry. Chemistry-based defects on the steel strips can vary in composition and generally consist of reaction products with the steel substrate. First big category of widely occurring chemistry-based defects is corrosion or oxidation, second contamination with alien matter and third defect category is related to carbon sediments. A number of different surface chemistry-based defects are related to annealing process. Common problem, that occurs in communication is, that identical defects are often indicated by different names and identical names are given for different defects. In the present study an overview including possible causes of three types of the continuous chemistry-based defects situated on the steel strip edges, that appeared to be the same at first glance, is presented: carbon edge deposit, low reflectivity band and annealed border.
2

Ipser, Herbert. "A3B Intermetallics: Defect chemistry and nonstoichiometry." Pure and Applied Chemistry 79, no. 10 (January 1, 2007): 1675–89. http://dx.doi.org/10.1351/pac200779101675.

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The defect chemistry of different ordered intermetallic compounds with the A3B stoichiometry was investigated. Three groups were distinguished according to their crystal structure: L12 compounds (Ni3Al, Ni3Ga, Pt3Ga, Pt3In), D019 compounds (Ti3Al), and D03 compounds (Fe3Al, Ni3Sb). Statistical-thermodynamic models were derived based on a Wagner-Schottky approach, and the calculated activity curves (thermodynamic activity vs. composition) were compared with experimental activity data. In this way, we attempted to obtain at least estimated values for the energies of formation of the different types of point defects present in the corresponding compound, both as configurational defects (which are responsible for nonstoichiometry) and as thermal defects. In the majority of cases, thermodynamic activities had to be determined experimentally in the present study, using either an emf method with a solid electrolyte (Ni3Ga, Pt3Ga, Pt3In, Fe3Al) or a Knudsen cell-mass spectrometric method (Ni3Sb).
3

Kovalevsky, Andrei V., Myriam H. Aguirre, Sascha Populoh, Sonia G. Patrício, Nuno M. Ferreira, Sergey M. Mikhalev, Duncan P. Fagg, Anke Weidenkaff, and Jorge R. Frade. "Designing strontium titanate-based thermoelectrics: insight into defect chemistry mechanisms." Journal of Materials Chemistry A 5, no. 8 (2017): 3909–22. http://dx.doi.org/10.1039/c6ta09860f.

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The work establishes a closer link between the defect chemistry and thermoelectric properties of strontium titanate-based materials, by uncovering particular roles of various defects in electronic and thermal transport.
4

Meggiolaro, Daniele, Silvia G. Motti, Edoardo Mosconi, Alex J. Barker, James Ball, Carlo Andrea Riccardo Perini, Felix Deschler, Annamaria Petrozza, and Filippo De Angelis. "Iodine chemistry determines the defect tolerance of lead-halide perovskites." Energy & Environmental Science 11, no. 3 (2018): 702–13. http://dx.doi.org/10.1039/c8ee00124c.

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Ayoub, Irfan, Vijay Kumar, Reza Abolhassani, Rishabh Sehgal, Vishal Sharma, Rakesh Sehgal, Hendrik C. Swart, and Yogendra Kumar Mishra. "Advances in ZnO: Manipulation of defects for enhancing their technological potentials." Nanotechnology Reviews 11, no. 1 (January 1, 2022): 575–619. http://dx.doi.org/10.1515/ntrev-2022-0035.

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Abstract This review attempts to compile the physics and chemistry of defects in zinc oxide (ZnO), at both, the fundamental and application levels. The defects, either inherent ones or introduced externally, have broadened the ZnO material field in various directions. The ZnO material exhibits many defect-attributed properties leading to broad technological applications: electronic and optoelectronic devices, sensors, optical components, ceramic industry, biomedical, catalysis, lightening, etc. Considering the huge defect-dependent technological scopes, the ZnO material is constantly engineered for various defects, and corresponding functionalities are tailored with respect to particular applications. The functional properties of ZnO are strongly influenced by the defects, and as a result, the defect engineering of the ZnO materials has remained an important motivation in materials science and engineering in terms of localized defects, extended defects, impurities, and surface defects, etc. A detailed characterization of these defects seems to be an essential part of any research area. The correlations of the microstructural characteristics with electrical and optical properties of ZnO are then a natural step for further facilitating an efficient way toward advanced ZnO-based materials and devices. The present review is an effort to shed light on the defects of ZnO, properties, theoretical aspects, and corresponding applications.
6

Götze, Jens, Yuanming Pan, and Axel Müller. "Mineralogy and mineral chemistry of quartz: A review." Mineralogical Magazine 85, no. 5 (September 28, 2021): 639–64. http://dx.doi.org/10.1180/mgm.2021.72.

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AbstractQuartz (trigonal, low-temperature α-quartz) is the most important polymorph of the silica (SiO2) group and one of the purest minerals in the Earth crust. The mineralogy and mineral chemistry of quartz are determined mainly by its defect structure. Certain point defects, dislocations and micro-inclusions can be incorporated into quartz during crystallisation under various thermodynamic conditions and by secondary processes such as alteration, irradiation, diagenesis or metamorphism. The resulting real structure is a fingerprint of the specific physicochemical environment of quartz formation and also determines the quality and applications of SiO2 raw materials. Point defects in quartz can be related to imperfections associated with silicon or oxygen vacancies (intrinsic defects), to different types of displaced atoms, and/or to the incorporation of foreign ions in lattice sites and interstitial positions (extrinsic defects). Due to mismatch in charges and ionic radii only a limited number of ions can substitute for Si4+ in the crystal lattice or can be incorporated in interstitial positions. Therefore, most impurity elements in quartz are present at concentrations below 1 ppm. The structural incorporation in a regular Si4+ lattice site has been proven for Al3+, Ga3+, Fe3+, B3+, Ge4+, Ti4+, P5+ and H+, of which Al3+ is by far the most common and typically the most abundant. Unambiguous detection and characterisation of defect structures in quartz are a technical challenge and can only be successfully realised by a combination of advanced analytical methods such as electron paramagnetic resonance (EPR) spectroscopy, cathodoluminescence (CL) microscopy and spectroscopy as well as spatially resolved trace-element analysis such as laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) and secondary-ion mass spectrometry (SIMS). The present paper presents a review of the state-of-the-art knowledge concerning the mineralogy and mineral-chemistry of quartz and illustrates important geological implications of the properties of quartz.
7

Luo, Yang, and Yinghong Wu. "Defect Engineering of Nanomaterials for Catalysis." Nanomaterials 13, no. 6 (March 21, 2023): 1116. http://dx.doi.org/10.3390/nano13061116.

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8

Chiodelli, G., U. Anselmi-Tamburini, M. Arimondi, G. Spinolo, and G. Flor. "Defect Chemistry of “BaCuO2” II. Transport Properties and Nature of Defects." Zeitschrift für Naturforschung A 50, no. 11 (November 1, 1995): 1059–66. http://dx.doi.org/10.1515/zna-1995-1113.

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Abstract The charge transport properties of "BaCuO2" with 88:90 (Ba :Cu) cation ratio were characterized by thermopower, electrical conductivity and ionic transport number measurements in a wide range of temperature and oxygen partial pressure conditions. The nature of carriers is always represented by small polarons due to self-trapping of the electronic holes generated by the oxygen non-stoichiometry equilibrium. Some anomalies in carrier mobility as a function of temperature are shown not to be related to incomplete ionization of oxygen atoms on interstitial sites
9

Withers, Ray, Jeffrey Sellar, Michael O'Keeffe, and Stephen Hyde. "Bruce Godfrey Hyde 1925–2014." Historical Records of Australian Science 26, no. 2 (2015): 179. http://dx.doi.org/10.1071/hr15006.

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Bruce Hyde made seminal contributions to modern solid state chemistry, in particular to the understanding and characterization of non-stoichiometry and structural complexity in the solid state. His work showed unequivocally that non-stoichiometric crystalline materialswere often much more highly ordered than previously believed, that the ‘point defects' of conventional wisdom were in fact ordered into extended defects and that these defects were themselves ordered into structures of complexities hitherto unimagined. His deep understanding of crystal chemistry and structural relationships is apparent in his two co-authored books with his closest colleagues, Sten Andersson and Michael O'Keeffe. It also led to his mentoring an entire generation of younger Australian (and international) solid state chemists.
10

Stemmer, S., G. Duscher, E. M. James, M. Ceh, and N. D. Browning. "Atomic Scale Structure-Property Relationships of Defects and Interfaces in Ceramics." Microscopy and Microanalysis 4, S2 (July 1998): 556–57. http://dx.doi.org/10.1017/s143192760002290x.

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The evaluation of the two dimensional projected atom column positions around a defect or an interface in an electronic ceramic, as it has been performed in numerous examples by (quantitative) conventional high-resolution electron microscopy (HRTEM), is often not sufficient to relate the electronic properties of the material to the structure of the defect. Information about point defects (vacancies, impurity atoms), and chemistry or bonding changes associated with the defect or interface is also required. Such complete characterization is a necessity for atomic scale interfacial or defect engineering to be attained.One instructive example where more than an image is required to understand the structure property relationships, is that of grain boundaries in Fe-doped SrTi03. Here, the different formation energies of point defects cause a charged barrier at the boundary, and a compensating space charge region around it. The sign and magnitude of the barrier depend very sensitively on the atomic scale composition and chemistry of the boundary plane.
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You might also be interested in the extended bibliographies on the topic 'Defects Chemistry' for particular source types:
Journal articles Dissertations / Theses Books

Dissertations / Theses on the topic "Defects Chemistry":

1

Cromack, Keith Richard. "Photo-induced magnetic defects in conducting polymers." The Ohio State University, 1991. http://rave.ohiolink.edu/etdc/view?acc_num=osu1343059111.

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Józefowicz, Mikolaj Edward. "Structure and long-lived defects in polyanilines." The Ohio State University, 1991. http://rave.ohiolink.edu/etdc/view?acc_num=osu1343400785.

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3

Cliffe, Matthew James. "Disorder and defects in functional molecular frameworks." Thesis, University of Oxford, 2015. http://ora.ox.ac.uk/objects/uuid:cd827bc8-b3dd-4fda-bdb8-f0dc893d66c2.

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This Thesis explores the role of structural defects and disorder and their relationship to experimental data, with a particular emphasis on molecular framework materials. The question of how we can build atomistic models of amorphous materials from experimental data without needing to make system-specific assumptions is addressed. The role of 'structural invariance', i.e. the limited range of distinct local atomic environments within a material, as a restraint within reverse Monte Carlo refinement (RMC) is investigated. The operation of these invariance restraints operate is shown to be system-dependent and the challenges associated with effective refinement, e.g. configurational 'jamming', are also investigated. A generalisation to the 'structural simplicity', i.e. the simplest model, holding all else constant, is most likely to be correct. Three new metrics of structural simplicity are proposed: two intrinsically three-dimensional measures of local geometric invariance and one measure of local symmetry. These metrics are shown to robustly quantify the configurational quality. The ability of these metrics to act as effective restraints for the RMC refinement of amorphous materials is demonstrated by the construction of the first data-driven tetrahedral models of amorphous silicon. The role of defects and disorder within metal–organic frameworks (MOFs) is investigated through the canonical MOF UiO-66(Hf). Through a combination of techniques, including X-ray diffuse scattering, anomalous diffraction, total scattering and electron diffraction measurements, the existence of correlated metal-cluster absences in UiO-66(Hf) is demonstrated. Furthermore the ability to synthetically tune both the interactions and concentration of defects is shown. The thermomechanical properties of defective UiO-66(Hf) are also examined. UiO-66(Hf) is shown to rapidly densify by up to 5% (ΔV/V ) on ligand elimination. The resultant densified phase exhibits colossal (≥100MK-1) volumetric negative thermal expansion (NTE); the largest reported value for any MOF. Finally, the capability to tune the physical properties of MOFs through defect incorporation is demonstrated through the defect-dependence of both the densification and the NTE.
4

Lee, Lawrence Yoon Suk 1972. "Probing and controlling defects in self-assembled monolayers." Thesis, McGill University, 2006. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=102674.

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This thesis is focused on the development of a tool for probing defects in self-assembled monolayers (SAMs). Such a tool is necessary for the detailed understanding of fundamental issues in SAM composition and structure. The electrochemical properties of single component and binary ferrocenylalkylthiol SAMs on polycrystalline gold (FcC12S-Au and FcC12S-/CH 3RS-Au) have been investigated in detail. The complex voltammetry obtained for various mixtures of FcC12S-Au SAMs is shown to be linked to local electrostatics caused by the formation of the ferrocenium ion. A procedure involving a Gaussian-Lorentzian fit is used to deconvolute the two peaks consistently observed in the SAMs when the surface mole fraction of the FcC12S-Au ( csurfFc ) ≥ 0.2. The lower potential (Eº' = 250 mV) and higher potential (Eº' = 350 mV) voltammetric peaks are thus assigned to Fc moieties in "isolated" and "clustered" states, respectively. Use of this method to better understand SAM structure is demonstrated by distinguishing the degree of homogeneity in two binary SAMs of similar composition.
This characteristic electrochemical property of FcC12S-Au system allows for the quantification of defects in SAMs. This is important because coverage defects, or voids in alkylthiol SAMs, are a critical component of electron transfer mechanisms of soluble redox probes. Short time exposure of a defective SAM to FcC12SH leads to a quantifiable defect-related Fc coverage (GammaFc), with GammaFc < 1% being readily measurable. Using FcC12SH as a label, a number of alkylthiol SAM preparation conditions have been assessed.
FcC12SH is further used to probe the progress of the important alkylthiol-for-alkylthiol exchange reaction in SAMs. It is shown that variation of chain length, reaction temperature, terminal group, applied potential, and the initial defect density determines the extent and the rate of the exchange reaction. Kinetics studies of binary (FcC12S-/CH3RS-Au) SAM formation via co-incubation reveal that although csurfFc is initially close to the solution mole fraction of the FcC12 SH ( csolnFc ), the subsequent exchange reaction leads to a csurfFc which is often quite different from csolnFc .
Finally, the FcC12SH probe is used to further study the reductive voltammetric desorption of alkylthiol SAMs. Defects in a C14S-Au SAM created by excursions to desorptive reduction potentials were quantified by use of the FcC12SH label. A reductive desorption potential followed by re-adsorption, applied to a binary (FcC12S-/C14S-Au) SAM, results in mixing of the phase separated components of the binary SAM.
5

Pressé, Steve 1981. "Role of fluctuations and defects in select condensed matter problems." Thesis, Massachusetts Institute of Technology, 2008. http://hdl.handle.net/1721.1/43774.

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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Chemistry, 2008.
Page 122 blank. Vita.
Includes bibliographical references.
Defects and fluctuations dominate both static and dynamical properties of systems in the condensed phase. In this work, we focus on three such examples. Firstly, we model the effect of proton fluctuations on the rate of electron transfer in the condensed phase through an electron donor-acceptor assembly linked via an H-bonding bridge. The model suggests that it is possible for the electron transfer rate through a deuterated H-bonding assembly to exceed the rate through a protonated H-bonding bridge at low temperature, consistent with experimental findings. Next, we consider the convergence properties of Jarzynski's non-equilibrium work relation. This relation expresses the free energy change of a system, onto which finite-time work is done, as an ensemble average over all possible trajectories of the system. We quantify the regime of applicability of this equality by considering the role of rare fluctuations which dominate the work average of entropy generating processes. Lastly, we consider fluorophore lifetime variations arising when single molecules are placed near non-planar metallic surfaces. We compute the exact first order self-fields of vertical dipoles located above locally curved perfectly conducting surfaces by invoking a small slope phase perturbation technique. The results suggest that smooth perturbations lead to deviations from the image theory results extensively used to interpret the experimentally observed single molecule lifetime changes.
by Steve Pressé.
Ph.D.
6

Mottishaw, Sinead. "Investigations of the nature, properties and distribution of defects in diamond." Thesis, University of Warwick, 2017. http://wrap.warwick.ac.uk/101511/.

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This thesis presents investigations into the nature, properties and distribution of defects in diamond grown by the methods of chemical vapour deposition (CVD) and high pressure, high temperature (HPHT) synthesis. The experimental techniques used include electron paramagnetic resonance, optical absorption, cathodoluminescence, photoluminescence and secondary ion mass spectroscopy (SIMS). The optical spin polarisation of the neutral silicon vacancy defect (SiV0) was shown to be strongly enhanced by resonant excitation at the zero-phonon energy, although there was significant sample to sample variation in the magnitude. The spin polarisation mechanism is different to that observed for the negatively charged nitrogen vacancy defect in diamond and more than one mechanism may be generating spin polarisation. The spin-lattice relaxation time (T1) of the SiV0 ground state was found to change by six orders of magnitude between room temperature and 11 K, where T1 exceeded 25 seconds. At room temperature the achievable optical ground state spin polarisation is limited by the rapid spin-lattice relaxation. Irradiation and annealing studies of silicon doped CVD diamond samples showed that the silicon vacancy concentration can be increased by irradiation and annealing. However, the same processing conditions can also reduce the concentration of grown-in silicon vacancy defects. This work suggests that the relative incorporation efficiency of silicon in different forms in homoepitaxial CVD diamond may depend on the orientation of the substrate, and that the details of post growth silicon vacancy defect production, especially in boron doped diamond, are not yet well understood. HPHT samples in which the13 C isotopic abundance had been increased up to approximately 10% were studied. The variation of the abundance of13 C with distance from the seed was studied using Raman spectroscopy and SIMS, and the nitrogen incorporation by infrared microscopy. Possible explanations of the variations in both are discussed. The incorporation of point and extended defects into diamond grown by heteroepitaxial CVD was studied in a nitrogen doped sample and another grown with efforts to exclude nitrogen. The samples were highly birefringent when observed through cross-polarisers and exhibited strong dislocation related photoluminescence, suggesting significant concentrations of dislocations and dislocation bundles. The nitrogen doped heteroepitaxial CVD sample contained point defects in relative concentrations typically observed in nitrogen doped homoepitaxial CVD diamond; the total nitrogen impurity concentration exceeded 2,000 ppb, whereas in the intrinsic heteroepitaxial CVD sample it was less than a few ppb. Both samples contained a significant concentration of silicon vacancy defects and the photoluminescence spectra indicated that the point defects were subject to significant strain arising from both extended and point defects.
7

Roy, Santanu. "Spectroscopic study of defects in cadmium selenide quantum dots (QDS) and cadmium selenide nanorods (NRS)." Diss., Kansas State University, 2013. http://hdl.handle.net/2097/16118.

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Doctor of Philosophy
Department of Chemistry
Viktor Chikan
Ever depleting sources of fossil fuel has triggered more research in the field of alternate sources of energy. Over the past few years, CdSe nanoparticles have emerged as a material with a great potential for optoelectronic applications because of its easy exciton generation and charge separation. Electronic properties of CdSe nanoparticles are highly dependent on their size, shape and electronic environment. The main focus of this research is to explore the effect of different electronic environments on various spectroscopic properties of CdSe nanoparticles and link this to solar cell performance. To attain that goal, CdSe quantum dots (QDs) and nanorods (NRs) have been synthesized and either doped with metal dopants or embedded in polymer matrices. Electronic properties of these nanocomposites have been studied using several spectroscopic techniques such as absorption, photoluminescence, time-resolved photoluminescence, confocal microscopy and wide field microscopy. Indium and tin are the two metal dopants that have been used in the past to study the effect of doping on conductivity of CdSe QDs. Based on the photoluminescence quenching experiments, photoluminescence of both indium and tin doped samples suggest that they behave as n-type semiconductors. A comparison between theoretical and experimental data suggests that energy levels of indium doped and tin doped QDs are 280 meV and 100 meV lower than that of the lowest level of conduction band respectively. CdSe nanorods embedded in two different polymer matrices have been investigated using wide field fluorescence microscopy and confocal microscopy. The data reveals significant enhancement in bandedge luminescence of NRs in the vicinity of a conjugated polymer such as P3HT. Photoactive charge transfer from polymers to the surface traps of NRs may account for the observed behavior. Further study shows anti-correlation between bandedge and trap state emission of CdSe NRs. A recombination model has been proposed to explain the results. The origin of traps is also investigated and plausible explanations are drawn from the acquired data.
8

Srinivasan, K. "FDAS : a knowledge-based framework for analysis of defects in woven textile structures." Thesis, Georgia Institute of Technology, 1990. http://hdl.handle.net/1853/8671.

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Roberts, Sean T. (Sean Thomas). "Hydrogen bond rearrangements and the motion of charge defects in water viewed using multidimensional ultrafast infrared spectroscopy." Thesis, Massachusetts Institute of Technology, 2010. http://hdl.handle.net/1721.1/57678.

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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Chemistry, February 2010.
"December 2009." Cataloged from PDF version of thesis. Vita.
Includes bibliographical references.
Compared with other molecular liquids, water is highly structured due to its ability to form up to four hydrogen bonds to its nearest neighbors, resulting in a tetrahedral network of molecules. However, this network is highly dynamic, exhibiting fluctuations and rearrangements that take place on femtosecond to picosecond time scales. The transport of excess protons and proton holes in water makes exclusive use of water's hydrogen bonding network. Compared to ions of similar size and charge density, both hydronium and hydroxide ions exhibit anomalously high diffusion rates due to the fact that water molecules that neighbor these ions can undergo a proton transfer reaction with the ion. This allows the structural diffusion of the ion to occur apart from the displacement of individual water molecules. In this thesis we adopt a joint experimental and theoretical approach to characterize the fluctuations of water's hydrogen bonding network and how these fluctuations act to drive the structural diffusion of the aqueous hydroxide ion. The experimental data that we present consists of a series of ultrafast nonlinear infrared spectroscopies, in particular two-dimensional infrared spectroscopy (2D IR), applied to the O-H stretching transition of a dilute solution of HOD in NaOD/D20. The frequency of the O-H stretch, (OH, is highly sensitive to the configuration of its hydrogen bonding partner. 2D IR spectroscopy allows us to measure rapid shifts in OH that reveal time scales for changes in the local environment of the HOD molecule.
(cont.) The calculation of 2D IR spectra from molecular dynamics simulations then allows us to make a direct connection between the results of our experiments and the underlying dynamics of the system that drive both hydrogen bond exchange and the structural diffusion of the hydroxide ion. 2D IR spectra recorded for dilute HOD in D20 show a strong asymmetry, preferentially broadening in the frequency region indicative of strained or broken hydrogen bonds, indicating that these configurations are unstable and quickly return to a hydrogen bond. The time scale over which the 2D spectra broaden, ~60 fs, is similar to the librational period of water and suggests that molecules exchange hydrogen bonding partners though rapid, large amplitude rotations. Molecular dynamics simulations find that the transition state for hydrogen bond exchange resembles a bifurcated hydrogen bond. In roughly half of the examined exchange events, a second solvation shell water molecule inserts across the breaking hydrogen bond. This suggests that hydrogen bond rearrangements are tied to the restructuring of a water molecule's solvation shell. Upon the addition of NaOD to HOD/D20 solution, a large absorption continuum appears to the low frequency side of the O-H stretch due to the formation of strong hydrogen bonds between HOD molecules and OD ions. At early waiting times, 2D IR spectra show large, offdiagonal intensity in this frequency range that rapidly relaxes within ~110 fs.
(cont.) Modeling using an empirical valence bond simulation (MS-EVB) model of aqueous NaOH suggests that as the 0-H stretching potential symmetrizes during proton transfer events, overtone transitions of the shared proton contribute strongly to 2D spectra. The rapid loss of offdiagonal intensity results from the spectral sweeping of these vibrational overtones as the solvent modulates the motion of the shared proton. The collective electric field of the solvent is found to be an appropriate reaction coordinate for the formation and modulation of shared proton states. Over picosecond waiting times, spectral features appear in the 2D IR spectra that are indicative of the exchange of population between OH~ ions and HOD molecules due to proton transfer. The construction of a spectral fitting model gives a lower bound of 3 ps for this exchange. Calculations of structural parameters following proton exchange using the MS-EVB simulation model suggest that the observed exchange process corresponds to the formation and breakage of hydrogen bonds donated by the HOD/OD~ pair formed as a result of the proton transfer. A full description of the structural diffusion of the hydroxide ion requires both a description of the local hydrogen bonding structure of the ion as well as the dielectric fluctuations of the surrounding solvent.
by Sean T. Roberts.
Ph.D.
10

Jensen, Stephen C. "The Role of Interstitials and Surface Defects on Oxidation and Reduction Reactions on Titania." Thesis, Harvard University, 2013. http://dissertations.umi.com/gsas.harvard:10768.

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This thesis focuses on understanding the influence of defect sites in titanium dioxide that drive many types of thermal and photochemical reactions. Two of the most common defects in vacuum are titanium interstitials and oxygen vacancies. Molecular oxygen fills oxygen vacancies and creates oxygen adatoms. We broadly investigate reduction and oxidation reactions of oxygenates driven by titanium interstitials and oxygen adatoms. First, we focus on the thermal chemistry of oxygen adatoms with butyrophenone and find that it reacts with the adatoms to form a strongly bound complex. The large difference in mobility between complexed and uncomplexed butyrophenone, and the corrugated nature of the \(TiO_2(110)\) surface plane, allows a confined one-dimensional gas to persist, which is characterized by scanning tunneling microscopy (STM). Next, we focus on the reductive coupling of benzaldehyde to stilbene that is driven by titanium interstitials. The diolate intermediate of the reaction is identified by STM and the thermodynamic preference of molecular oxygen to interact with titanium interstitials is exploited to selectively reverse the benzaldehyde diolate intermediates. Additionally, we investigate the photo-oxidative coupling of methanol to methyl formate, the photo-oxidation of butyrophenone and the photo-stability of benzoate. Finally, we identify a water splitting mechanism on reduced titania that creates oxygen adatoms. We demonstrate that the photo-generated oxygen adatoms thermally react with titanium interstitials to make TiOx islands and drive the photo-oxidation of formaldehyde and butyrophenone. Methods used include temperature programmed reaction spectroscopy, STM, and density functional theory.
Chemistry and Chemical Biology
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Books on the topic "Defects Chemistry":

1

Tilley, R. J. D. Defect crystal chemistry and its applications. Glasgow: Blackie, 1987.

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Kosuge, Kōji. Chemistry of non-stoichiometric compounds. Oxford: Oxford University Press, 1994.

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N, Schock Robert, ed. Point defects in minerals. Washington, D.C: American Geophysical Union, 1985.

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Gutoff, Edgar B. Coating and Drying Defects. New York: John Wiley & Sons, Ltd., 2006.

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Nowotny, J. Non-Stoichiometric Compounds: Surfaces, Grain Boundaries and Structural Defects. Dordrecht: Springer Netherlands, 1989.

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Gutoff, Edgar B. Coating and drying defects: Troubleshooting operating problems. 2nd ed. Hoboken, N.J: John Wiley & Sons, 2006.

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Gutoff, Edgar B. Coating and drying defects: Troubleshooting operating problems. New York: Wiley, 1995.

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Frank-Kamenetskaya, O. V. Atomic defects and crystal structure of minerals. Edited by Rozhdestvenskaya, I. V. (Ira V.) and Frank-Kamenet︠s︡kiĭ V. A. 2nd ed. Saint Petersburg: Yanus, 2004.

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Sohar, Christian Rudolf. Lifetime Controlling Defects in Tool Steels. Berlin, Heidelberg: Springer-Verlag Berlin Heidelberg, 2011.

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McCluskey, Matthew D. Dopants and defects in semiconductors. Boca Raton, FL: Taylor & Francis, 2012.

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Book chapters on the topic "Defects Chemistry":

1

Ubic, Rick. "Point Defects." In Crystallography and Crystal Chemistry, 347–72. Cham: Springer International Publishing, 2024. http://dx.doi.org/10.1007/978-3-031-49752-0_16.

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Ubic, Rick. "Line Defects." In Crystallography and Crystal Chemistry, 373–95. Cham: Springer International Publishing, 2024. http://dx.doi.org/10.1007/978-3-031-49752-0_17.

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Moore, Elaine A., and Lesley E. Smart. "Defects and Nonstoichiometry." In Solid State Chemistry, 187–224. Fifth edition. | Boca Raton : CRC Press, [2021]: CRC Press, 2020. http://dx.doi.org/10.1201/9780429027284-5.

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Smart, Lesley, and Elaine Moore. "Defects and non-stoichiometry." In Solid State Chemistry, 159–218. Boston, MA: Springer US, 1995. http://dx.doi.org/10.1007/978-1-4899-6830-2_5.

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Cerofolini, Gianfranco, and Laura Meda. "Equilibrium Defects." In Physical Chemistry of, in and on Silicon, 15–24. Berlin, Heidelberg: Springer Berlin Heidelberg, 1989. http://dx.doi.org/10.1007/978-3-642-73504-2_3.

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Zhu, Xuefeng, and Weishen Yang. "Defects and Diffusion." In Green Chemistry and Sustainable Technology, 11–48. Berlin, Heidelberg: Springer Berlin Heidelberg, 2016. http://dx.doi.org/10.1007/978-3-662-53534-9_2.

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Carter, C. Barry, and M. Grant Norton. "Characterizing Structure, Defects, and Chemistry." In Ceramic Materials, 159–83. New York, NY: Springer New York, 2012. http://dx.doi.org/10.1007/978-1-4614-3523-5_10.

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Kröger, F. A. "Point Defects in Solids: Physics, Chemistry, and Thermodynamics." In Point Defects in Minerals, 1–17. Washington, D. C.: American Geophysical Union, 2013. http://dx.doi.org/10.1029/gm031p0001.

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Kleman, M. "Defects in Quasicrystals." In Physics and Chemistry of Finite Systems: From Clusters to Crystals, 199–210. Dordrecht: Springer Netherlands, 1992. http://dx.doi.org/10.1007/978-94-017-2645-0_23.

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Chadwick, A. V., and J. Corish. "Defects and Matter Transport in Solid Materials." In New Trends in Materials Chemistry, 285–318. Dordrecht: Springer Netherlands, 1997. http://dx.doi.org/10.1007/978-94-011-5570-0_10.

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Conference papers on the topic "Defects Chemistry":

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Sharia, Onise, Maija M. Kuklja, Mark Elert, Michael D. Furnish, William W. Anderson, William G. Proud, and William T. Butler. "EFFECT OF DEFECTS ON INITIATION OF CHEMISTRY IN HMX." In SHOCK COMPRESSION OF CONDENSED MATTER 2009: Proceedings of the American Physical Society Topical Group on Shock Compression of Condensed Matter. AIP, 2009. http://dx.doi.org/10.1063/1.3295142.

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Dean, B. E., C. J. Johnson, S. C. McDevitt, G. T. Neugebauer, J. L. Sepich, R. C. Dobbyn, M. Kuriyama, J. Elllsworth, H. R. Vydyanath, and J. J. Kennedy. "Correlation of HgCdTe epilayer defects with underlying substrate defects by synchrotron x-ray topography." In Physics and chemistry of mercury cadmium telluride and novel IR detector materials. AIP, 1991. http://dx.doi.org/10.1063/1.41061.

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Wang, Chenwei, Yue Li, Guoqiang Song, Zhaoqing Huo, Jia Liu, and Yuling Liu. "Role of Slurry Chemistry for Defects Reduction During Barrier CMP." In 2020 China Semiconductor Technology International Conference (CSTIC). IEEE, 2020. http://dx.doi.org/10.1109/cstic49141.2020.9282561.

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Wright, John C. "Site selective laser spectroscopy of defects in solids." In OSA Annual Meeting. Washington, D.C.: Optica Publishing Group, 1989. http://dx.doi.org/10.1364/oam.1989.mgg3.

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Abstract:
When crystals are doped with aliovalent ions, defects are formed to balance the charge mismatch. Many defect structures can form from different combinations of the dopant and charge compensating ions. Site selective spectroscopy can be used to selectively examine specific structures using fluorescent dopant ions whose crystal field splittings reflect the local environment. The fluorescence is used to measure absolute site concentrations, and follow the concentrations as the crystals are modified by changing dopants, concentrations, crystal temperature, or the partial pressure of equilibrating gases. The individual defect sites can be identified and the distribution of different defects can be described by models of the solid state chemistry. The dynamics of defect formation can also be followed to acquire a detailed microscopic description of the defects. Sites with particularly favorable optical properties (radiative transition rates, energy transfer, quantum efficiency, etc.) can be optimized by appropriate processing conditions.
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Stashans, Arvids, Jean-Louis Calais, and Eugene Kotomin. "Quantum-chemical simulations of point defects in α-Al2O3." In The first European conference on computational chemistry (E.C.C.C.1). AIP, 1995. http://dx.doi.org/10.1063/1.47655.

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Wang, YuHuang. "Organic color center quantum defects in carbon nanotube semiconductors: progresses, challenges, and opportunities." In Physical Chemistry of Semiconductor Materials and Interfaces XXII, edited by Andrew J. Musser and Derya Baran. SPIE, 2023. http://dx.doi.org/10.1117/12.2677676.

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Sarma, Ch Amarnatha, Bollem Vamsi Krishna, L. M. L. Narayana Reddy, and P. Sree Lakshmi. "An inter-dıgıtal band-pass fılter wıth dual vıas in resonator and defects in ground sheet for S-band applıcatıons." In CHEMISTRY BEYOND BORDERS: INTERNATIONAL CONFERENCE ON PHYSICAL CHEMISTRY: The 1st Annual Meeting of the Physical Chemistry Division of the Indonesian Chemical Society. AIP Publishing, 2023. http://dx.doi.org/10.1063/5.0166041.

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Meggiolaro, Daniele. "A Theoretical Tour of Metal-Halide Perovskites Defects Chemistry: from Lead to Tin." In MATSUS23 & Sustainable Technology Forum València (STECH23). València: FUNDACIO DE LA COMUNITAT VALENCIANA SCITO, 2022. http://dx.doi.org/10.29363/nanoge.matsus.2023.376.

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KONONENKO, V. K., D. V. USHAKOV, and H. W. KUNERT. "EFFECTS OF DOPING AND NONRADIATIVE DEFECTS IN GaAs SUPERLATTICES." In Physics, Chemistry and Application of Nanostructures - Reviews and Short Notes to Nanomeeting 2003. WORLD SCIENTIFIC, 2003. http://dx.doi.org/10.1142/9789812796738_0010.

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Moro, Stefania, Giovanni Costantini, and Michael Sommer. "Quantitative characterisation of conjugated polymers: mass distribution and polymerisation defects determined by molecular scale imaging." In Physical Chemistry of Semiconductor Materials and Interfaces XXII, edited by Andrew J. Musser and Derya Baran. SPIE, 2023. http://dx.doi.org/10.1117/12.2677311.

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Reports on the topic "Defects Chemistry":

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Ballance, Joan B., Mitsuo Kawabe, Timothy D. Sands, Eicke R. Weber, and R. S. Williams. Chemistry and Defects in Semiconductor Heterostructures. Materials Research Society Symposium Proceedings. Volume 148. Fort Belvoir, VA: Defense Technical Information Center, May 1990. http://dx.doi.org/10.21236/ada229585.

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Maxey. L51427 ERW Weld Zone Characteristics. Chantilly, Virginia: Pipeline Research Council International, Inc. (PRCI), June 1992. http://dx.doi.org/10.55274/r0011187.

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Abstract:
The objective of this research project was to determine the fatigue characteristics of the weld zone of electric resistance welded (ERW) pipe. The project involved: (1) characterizing pipe samples in terms of initial defects, tensile and yield strength, chemistry, and fracture toughness, (2) evaluating the fatigue crack growth of base metal and the weld zone in air and a 3.5 wt% NaCl solution, and (3) evaluating the fatigue crack growth of machined defects in the weld zone of ERW pipe subjected to cyclic pressure loading. This study found that the weld zone and base metal exhibit the same fatigue crack growth rates, the weld zone is not more susceptible to corrosion fatigue damage, and the greatest variability in ERW pipe fatigue behavior lies in the initial defect distribution.
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Singel, David J. Electron Transfer Chemistry in Optical Materials: An EPR Investigation of Radiation-Induced Defects in Chemically Modified Materials. Fort Belvoir, VA: Defense Technical Information Center, January 2001. http://dx.doi.org/10.21236/ada387336.

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Harmer, Martin P., and Donald M. Smyth. Nanostructure and Defect Chemistry of Relaxor Ferroelectrics. Fort Belvoir, VA: Defense Technical Information Center, July 1988. http://dx.doi.org/10.21236/ada207217.

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Anil V. Virkar. Electrically Conductive, Corrosion-Resistant Coatings Through Defect Chemistry for Metallic Interconnects. Office of Scientific and Technical Information (OSTI), December 2006. http://dx.doi.org/10.2172/920189.

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Kerr, Lei L., David C. Look, and Zhaoqiang Fang. Defect Chemistry Study of Nitrogen Doped ZnO Thin Films. Final report. Office of Scientific and Technical Information (OSTI), November 2009. http://dx.doi.org/10.2172/1060189.

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