Quantum Mechanical First Principles Calculations of the Electronic and Magnetic Structure of Fe-Bearing Rock-Forming Silicates

Quantum Mechanical First Principles Calculations of the Electronic and Magnetic Structure of Fe-Bearing Rock-Forming Silicates

Author: Danylo Zherebetskyy

Publisher: Universal-Publishers

Published: 2010

Total Pages: 138

ISBN-13: 1599423162

DOWNLOAD EBOOK

The focus of this thesis is the study of the electronic and magnetic structure of three representative members of Fe-bearing rock-forming silicates, viz. orthoferrosilite (Fe2+2Si2O6), almandine (Fe2+3Al2(SiO4)3) and andradite (Ca3Fe3+2(SiO4)3). These minerals have attracted significant attention due to their abundance in the Earth's crust and mantle, and because crystallised silicates are main components of cosmic dust which is the most abundant raw material in the Universe. For this purpose quantum mechanical first principles electronic structure calculations are performed by the most efficient DFT method in the local spin-density approximation for calculating spectroscopic data: the spin-polarized self consistent charge Xa method. The specific feature and strength of these investigations consist in the theoretical characterization of these complex systems based on experimental results. This means that, on one hand, experimental spectroscopic and crystallographic data are being used to judge the reliability of the calculations, whereas, on the other hand, experimental data are interpreted and explained by the theoretical results. This work comprises seven chapters. After a brief introduction (Chapter 1) Chapter 2 describes the theoretical bases, ideas, approximations and advantages of the SCC- Xa method and basics of the art of cluster construction. Chapter 3 considers physical bases of crystal field theory, absorption, Mossbauer spectroscopy and magnetic interactions, as well as the calculation of spectroscopic data within the frame of the SCC-Xa method. In addition, tetragonally, trigonally and angularly distorted octahedral sites with various degrees of the distortions are calculated and analyzed. The electronic and magnetic structures of orthoferrosilite, almandine and andradite are described in the following chapters. In the case of orthoferrosilite the magnetic interactions between the iron spins within the ribbons and between neighboring ribbons are characterized. Two identical interpenetrating magnetic sublattices of circles of 10 edge-shared dodecahedra are revealed and characterized in almandine. The calculated spin structure explains and solves the controversy in the interpretation of the Mossbauer spectra of almandine below the Neel temperature. For andradite a model of the magnetic structure is proposed based on geometrical considerations and the calculated spin coupling constants for the various interaction pathways. According to this model, the magnetic structure of andradite consists of two frustrated equivalent magnetic sublattices. The spins of the Fe ions within each sublattice are coupled antiferromagnetically. The derived spin pattern explains two sextets in the Mossbauer spectra of andradite below the Neel temperature. Finally, the main results are summarized in Chapter 7.


Book Synopsis Quantum Mechanical First Principles Calculations of the Electronic and Magnetic Structure of Fe-Bearing Rock-Forming Silicates by : Danylo Zherebetskyy

Download or read book Quantum Mechanical First Principles Calculations of the Electronic and Magnetic Structure of Fe-Bearing Rock-Forming Silicates written by Danylo Zherebetskyy and published by Universal-Publishers. This book was released on 2010 with total page 138 pages. Available in PDF, EPUB and Kindle. Book excerpt: The focus of this thesis is the study of the electronic and magnetic structure of three representative members of Fe-bearing rock-forming silicates, viz. orthoferrosilite (Fe2+2Si2O6), almandine (Fe2+3Al2(SiO4)3) and andradite (Ca3Fe3+2(SiO4)3). These minerals have attracted significant attention due to their abundance in the Earth's crust and mantle, and because crystallised silicates are main components of cosmic dust which is the most abundant raw material in the Universe. For this purpose quantum mechanical first principles electronic structure calculations are performed by the most efficient DFT method in the local spin-density approximation for calculating spectroscopic data: the spin-polarized self consistent charge Xa method. The specific feature and strength of these investigations consist in the theoretical characterization of these complex systems based on experimental results. This means that, on one hand, experimental spectroscopic and crystallographic data are being used to judge the reliability of the calculations, whereas, on the other hand, experimental data are interpreted and explained by the theoretical results. This work comprises seven chapters. After a brief introduction (Chapter 1) Chapter 2 describes the theoretical bases, ideas, approximations and advantages of the SCC- Xa method and basics of the art of cluster construction. Chapter 3 considers physical bases of crystal field theory, absorption, Mossbauer spectroscopy and magnetic interactions, as well as the calculation of spectroscopic data within the frame of the SCC-Xa method. In addition, tetragonally, trigonally and angularly distorted octahedral sites with various degrees of the distortions are calculated and analyzed. The electronic and magnetic structures of orthoferrosilite, almandine and andradite are described in the following chapters. In the case of orthoferrosilite the magnetic interactions between the iron spins within the ribbons and between neighboring ribbons are characterized. Two identical interpenetrating magnetic sublattices of circles of 10 edge-shared dodecahedra are revealed and characterized in almandine. The calculated spin structure explains and solves the controversy in the interpretation of the Mossbauer spectra of almandine below the Neel temperature. For andradite a model of the magnetic structure is proposed based on geometrical considerations and the calculated spin coupling constants for the various interaction pathways. According to this model, the magnetic structure of andradite consists of two frustrated equivalent magnetic sublattices. The spins of the Fe ions within each sublattice are coupled antiferromagnetically. The derived spin pattern explains two sextets in the Mossbauer spectra of andradite below the Neel temperature. Finally, the main results are summarized in Chapter 7.


The Difference Electron Nanoscope

The Difference Electron Nanoscope

Author: Werner Lottermoser

Publisher: CRC Press

Published: 2017-06-26

Total Pages: 158

ISBN-13: 1351767666

DOWNLOAD EBOOK

This book deals with the difference electron nanoscope (DEN), whose principles have been invented and realised by the book author. The DEN is based on a smart combination of diffractometric and spectroscopic data and uses a visualisation of three-dimensional difference electron densities (in our case stemming from 3d orbitals) in order to obtain the key quantity involved, the electric field gradient (efg). However, the DEN is no machine, as the title of the book might infer. It is a computer program running on a fast computer system displaying 3D difference electron hyperareas floating in space and the relevant efg as a wire frame model within the unit cell of the sample involved. In this sense, it acts on a sub-nanometer scale (hence the term "nanoscope") and generates images of uncompared symmetrical and physical evidence—and beauty. For the first time, diffractometry and spectroscopy have been integrated for the common synergetic effects that may contribute to a better understanding of electric and magnetic interactions in a crystal. The experimental derivation of the common quantity, the efg, is not confined to iron-containing samples, as the use of Mössbauer spectroscopy might infer, but can also be determined by nuclear quadrupole resonance that is not confined to special nuclides. Hence, the DEN can be applied to a huge multitude of scientifically interesting specimens since the main method involved, diffractometry in a wide sense, has no general limitations at all. So it is a rather universal method, and the monograph might contribute to a wide distribution of the method in the scientific world. Has anyone seen a real orbital before: a real orbital distribution in a crystal unit cell together with its efg tensor ellipsoid? In this book, one can see it.


Book Synopsis The Difference Electron Nanoscope by : Werner Lottermoser

Download or read book The Difference Electron Nanoscope written by Werner Lottermoser and published by CRC Press. This book was released on 2017-06-26 with total page 158 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book deals with the difference electron nanoscope (DEN), whose principles have been invented and realised by the book author. The DEN is based on a smart combination of diffractometric and spectroscopic data and uses a visualisation of three-dimensional difference electron densities (in our case stemming from 3d orbitals) in order to obtain the key quantity involved, the electric field gradient (efg). However, the DEN is no machine, as the title of the book might infer. It is a computer program running on a fast computer system displaying 3D difference electron hyperareas floating in space and the relevant efg as a wire frame model within the unit cell of the sample involved. In this sense, it acts on a sub-nanometer scale (hence the term "nanoscope") and generates images of uncompared symmetrical and physical evidence—and beauty. For the first time, diffractometry and spectroscopy have been integrated for the common synergetic effects that may contribute to a better understanding of electric and magnetic interactions in a crystal. The experimental derivation of the common quantity, the efg, is not confined to iron-containing samples, as the use of Mössbauer spectroscopy might infer, but can also be determined by nuclear quadrupole resonance that is not confined to special nuclides. Hence, the DEN can be applied to a huge multitude of scientifically interesting specimens since the main method involved, diffractometry in a wide sense, has no general limitations at all. So it is a rather universal method, and the monograph might contribute to a wide distribution of the method in the scientific world. Has anyone seen a real orbital before: a real orbital distribution in a crystal unit cell together with its efg tensor ellipsoid? In this book, one can see it.


Chemistry of the rock-forming silicates

Chemistry of the rock-forming silicates

Author: J.J. Papike

Publisher:

Published: 1987

Total Pages:

ISBN-13:

DOWNLOAD EBOOK


Book Synopsis Chemistry of the rock-forming silicates by : J.J. Papike

Download or read book Chemistry of the rock-forming silicates written by J.J. Papike and published by . This book was released on 1987 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:


U.S. National Report 1987-1990

U.S. National Report 1987-1990

Author:

Publisher:

Published: 1991

Total Pages: 760

ISBN-13:

DOWNLOAD EBOOK


Book Synopsis U.S. National Report 1987-1990 by :

Download or read book U.S. National Report 1987-1990 written by and published by . This book was released on 1991 with total page 760 pages. Available in PDF, EPUB and Kindle. Book excerpt:


Essentials of Paleomagnetism

Essentials of Paleomagnetism

Author: Lisa Tauxe

Publisher: Univ of California Press

Published: 2010-03-19

Total Pages: 505

ISBN-13: 0520260317

DOWNLOAD EBOOK

"This book by Lisa Tauxe and others is a marvelous tool for education and research in Paleomagnetism. Many students in the U.S. and around the world will welcome this publication, which was previously only available via the Internet. Professor Tauxe has performed a service for teaching and research that is utterly unique."—Neil D. Opdyke, University of Florida


Book Synopsis Essentials of Paleomagnetism by : Lisa Tauxe

Download or read book Essentials of Paleomagnetism written by Lisa Tauxe and published by Univ of California Press. This book was released on 2010-03-19 with total page 505 pages. Available in PDF, EPUB and Kindle. Book excerpt: "This book by Lisa Tauxe and others is a marvelous tool for education and research in Paleomagnetism. Many students in the U.S. and around the world will welcome this publication, which was previously only available via the Internet. Professor Tauxe has performed a service for teaching and research that is utterly unique."—Neil D. Opdyke, University of Florida


Advanced Mineralogy

Advanced Mineralogy

Author: A.S. Marfunin

Publisher: Springer

Published: 1994-08-23

Total Pages: 588

ISBN-13: 9783540572541

DOWNLOAD EBOOK

All existing introductory reviews of mineralogy are written accord ing to the same algorithm, sometimes called the "Dana System of Mineralogy". Even modern advanced handbooks, which are cer tainly necessary, include basic data on minerals and are essentially descriptive. When basic information on the chemistry, structure, optical and physical properties, distinguished features and para genesis of 200-400 minerals is presented, then there is practically no further space available to include new ideas and concepts based on recent mineral studies. A possible solution to this dilemma would be to present a book beginning where introductory textbooks end for those already famil iar with the elementary concepts. Such a volume would be tailored to specialists in all fields of science and industry, interested in the most recent results in mineralogy. This approach may be called Advanced Mineralogy. Here, an attempt has been made to survey the current possibilities and aims in mineral matter investigations, including the main characteristics of all the methods, the most important problems and topics of mineral ogy, and related studies. The individual volumes are composed of short, condensed chap ters. Each chapter presents in a complete, albeit condensed, form specific problems, methods, theories, and directions of investigations, and estimates their importance and strategic position in science and industry.


Book Synopsis Advanced Mineralogy by : A.S. Marfunin

Download or read book Advanced Mineralogy written by A.S. Marfunin and published by Springer. This book was released on 1994-08-23 with total page 588 pages. Available in PDF, EPUB and Kindle. Book excerpt: All existing introductory reviews of mineralogy are written accord ing to the same algorithm, sometimes called the "Dana System of Mineralogy". Even modern advanced handbooks, which are cer tainly necessary, include basic data on minerals and are essentially descriptive. When basic information on the chemistry, structure, optical and physical properties, distinguished features and para genesis of 200-400 minerals is presented, then there is practically no further space available to include new ideas and concepts based on recent mineral studies. A possible solution to this dilemma would be to present a book beginning where introductory textbooks end for those already famil iar with the elementary concepts. Such a volume would be tailored to specialists in all fields of science and industry, interested in the most recent results in mineralogy. This approach may be called Advanced Mineralogy. Here, an attempt has been made to survey the current possibilities and aims in mineral matter investigations, including the main characteristics of all the methods, the most important problems and topics of mineral ogy, and related studies. The individual volumes are composed of short, condensed chap ters. Each chapter presents in a complete, albeit condensed, form specific problems, methods, theories, and directions of investigations, and estimates their importance and strategic position in science and industry.


Remote Compositional Analysis

Remote Compositional Analysis

Author: Janice L. Bishop

Publisher: Cambridge University Press

Published: 2019-11-28

Total Pages: 655

ISBN-13: 110718620X

DOWNLOAD EBOOK

Comprehensive overview of the spectroscopic, mineralogical, and geochemical techniques used in planetary remote sensing.


Book Synopsis Remote Compositional Analysis by : Janice L. Bishop

Download or read book Remote Compositional Analysis written by Janice L. Bishop and published by Cambridge University Press. This book was released on 2019-11-28 with total page 655 pages. Available in PDF, EPUB and Kindle. Book excerpt: Comprehensive overview of the spectroscopic, mineralogical, and geochemical techniques used in planetary remote sensing.


The Periodic Table

The Periodic Table

Author: Eric R. Scerri

Publisher: Oxford University Press, USA

Published: 2019

Total Pages: 503

ISBN-13: 019091436X

DOWNLOAD EBOOK

The periodic table of elements is among the most recognizable image in science. It lies at the core of chemistry and embodies the most fundamental principles of science. In this new edition, Eric Scerri offers readers a complete and updated history and philosophy of the periodic table. Written in a lively style to appeal to experts and interested lay-persons alike, The Periodic Table: Its Story and Its Significance begins with an overview of the importance of the periodic table and the manner in which the term "element" has been interpreted by chemists and philosophers across time. The book traces the evolution and development of the periodic table from its early beginnings with the work of the precursors like De Chancourtois, Newlands and Meyer to Mendeleev's 1869 first published table and beyond. Several chapters are devoted to developments in 20th century physics, especially quantum mechanics and and the extent to which they explain the periodic table in a more fundamental way. Other chapters examine the formation of the elements, nuclear structure, the discovery of the last seven infra-uranium elements, and the synthesis of trans-uranium elements. Finally, the book considers the many different ways of representing the periodic system and the quest for an optimal arrangement.


Book Synopsis The Periodic Table by : Eric R. Scerri

Download or read book The Periodic Table written by Eric R. Scerri and published by Oxford University Press, USA. This book was released on 2019 with total page 503 pages. Available in PDF, EPUB and Kindle. Book excerpt: The periodic table of elements is among the most recognizable image in science. It lies at the core of chemistry and embodies the most fundamental principles of science. In this new edition, Eric Scerri offers readers a complete and updated history and philosophy of the periodic table. Written in a lively style to appeal to experts and interested lay-persons alike, The Periodic Table: Its Story and Its Significance begins with an overview of the importance of the periodic table and the manner in which the term "element" has been interpreted by chemists and philosophers across time. The book traces the evolution and development of the periodic table from its early beginnings with the work of the precursors like De Chancourtois, Newlands and Meyer to Mendeleev's 1869 first published table and beyond. Several chapters are devoted to developments in 20th century physics, especially quantum mechanics and and the extent to which they explain the periodic table in a more fundamental way. Other chapters examine the formation of the elements, nuclear structure, the discovery of the last seven infra-uranium elements, and the synthesis of trans-uranium elements. Finally, the book considers the many different ways of representing the periodic system and the quest for an optimal arrangement.


Calculation of Equilibrium Constants for Isotopic Exchange Reactions

Calculation of Equilibrium Constants for Isotopic Exchange Reactions

Author: Jacob Bigeleisen

Publisher:

Published: 1947

Total Pages: 24

ISBN-13:

DOWNLOAD EBOOK


Book Synopsis Calculation of Equilibrium Constants for Isotopic Exchange Reactions by : Jacob Bigeleisen

Download or read book Calculation of Equilibrium Constants for Isotopic Exchange Reactions written by Jacob Bigeleisen and published by . This book was released on 1947 with total page 24 pages. Available in PDF, EPUB and Kindle. Book excerpt:


The Chemical Bond in Inorganic Chemistry

The Chemical Bond in Inorganic Chemistry

Author: Ian David Brown

Publisher:

Published: 2002

Total Pages: 289

ISBN-13: 0198508700

DOWNLOAD EBOOK

This book describes the bond valence model, a description of acid-base bonding which is becoming increasingly popular particularly in fields such as materials science and mineralogy where solid state inorganic chemistry is important. Recent improvements in crystal structure determination have allowed the model to become more quantitative. Unlike other models of inorganic chemical bonding, the bond valence model is simple, intuitive, and predictive, and can be used for analysing crystal structures and the conceptual modelling of local as well as extended structures. This is the first book to explore in depth the theoretical basis of the model and to show how it can be applied to synthetic and solution chemistry. It emphasizes the separate roles of the constraints of chemistry and of three-dimensional space by analysing the chemistry of solids. Many applications of the model in physics, materials science, chemistry, mineralogy, soil science, surface science, and molecular biology are reviewed. The final chapter describes how the bond valence model relates to and represents a simplification of other models of inorganic chemical bonding.


Book Synopsis The Chemical Bond in Inorganic Chemistry by : Ian David Brown

Download or read book The Chemical Bond in Inorganic Chemistry written by Ian David Brown and published by . This book was released on 2002 with total page 289 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book describes the bond valence model, a description of acid-base bonding which is becoming increasingly popular particularly in fields such as materials science and mineralogy where solid state inorganic chemistry is important. Recent improvements in crystal structure determination have allowed the model to become more quantitative. Unlike other models of inorganic chemical bonding, the bond valence model is simple, intuitive, and predictive, and can be used for analysing crystal structures and the conceptual modelling of local as well as extended structures. This is the first book to explore in depth the theoretical basis of the model and to show how it can be applied to synthetic and solution chemistry. It emphasizes the separate roles of the constraints of chemistry and of three-dimensional space by analysing the chemistry of solids. Many applications of the model in physics, materials science, chemistry, mineralogy, soil science, surface science, and molecular biology are reviewed. The final chapter describes how the bond valence model relates to and represents a simplification of other models of inorganic chemical bonding.