Search query: Chemical bonding in sulfide minerals

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abstract: An understanding of chemical bonding and electronic structure in sulfide minerals is central to any attempt at understanding their crystal structures, stabilities and physical properties. It is also an essential precursor to understanding reactivity through modeling surface structure at the molecular scale. In recent decades, there have been remarkable advances in first principles ab initio methods for the quantitative calculation of electronic structure. These advances have been made possible by the very rapid development of high performance computers. Several review volumes that chart the applications of these developments in mineralogy and geochemistry are available (Tossell and Vaughan 1992; Cygan and Kubicki 2001) An important feature of the sulfide minerals is the diversity of their electronic structures, as evidenced by their electrical and magnetic properties (see Pearce et al. 2006, this volume) Thus, sulfide minerals range from insulators through semiconductors to metals, and exhibit every type of magnetic behavior. This has presented problems for those attempting to develop bonding models for sulfides, and also led to certain misconceptions regarding the kinds of models that may be appropriate. In this chapter, chemical bonding and electronic structure models for sulfides are reviewed with emphasis on more recent developments. Although the fully ab initio quantitative methods are now capable of a remarkable degree of sophistication in terms of agreement with experiment and potential to interpret and predict behavior with varying conditions, both qualitative and more simplistic quantitative approaches will also be briefly discussed. This is because we believe that the insights which they provide are still helpful to those studying sulfide minerals. In addition to the application of electronic structure models and calculations to solid sulfides, work on sulfide mineral surfaces (Rosso and Vaughan 2006a,b) and solution complexes and clusters (Rickard and Luther 2006) are discussed in detail later
author_names: David J Vaughan

Kevin M Rosso
title: Chemical Bonding in Sulfide Minerals
year: 2006

abstract: Our knowledge and understanding of the electronic structure, chemical bonding, and physical properties of the chalcogenides of transition metals have advanced enormously over the last two decades. From the viewpoint of the theoretical solid state physicist or chemist these advances were driven by the orders of magnitude increases in computer power that have made quantitatively accurate calculations of electron band structure a routine possibility. Within this chapter we highlight a few such applications, concentrating on two groups of mineral sulfides: the transition metal dichalcogenides (including both the layer structure family and the pyrite/marcasite structures) and the tetrahedrite and related family of minerals. While the chapter focusses on the results provided by band structure calculations, it is recognised that these can only be convincing given the experimental back up provided by techniques such as ultraviolet or X ray photoemission and Auger electron studies (Vaughan and Tossell 1986)
author_names: David W Bullett
title: Chemical Bonding in Sulfide Minerals
year: 1994

abstract: The sulfur atom in sulfide minerals may have an argononic structure, with the sum of the covalent bonds and unshared pairs equal to 4 (with use of four spa orbitals) or a transargononic structure, with this sum greater than 4 (with use also of one or more 3d orbitals) Conclusions about the nature of the bonds and the structure of the sulfur atom can be drawn from the experimentally determined ligancies, bond lengths, and bond angles. A detailed discussion of realgar, orpiment, cinnabar, molybdenite, proustite, pyrargyrite, pyrostilpnite, sphalerite, wurtzite, greenockite, metacinnabarite, galena, baumhauerite, gratonite, binnite, covellite, sulvanite, mackinawite, pyrite, and marcasite leads to the conclusion that the principal structures of sulfur in these minerals are argononic with covalence 2, 3, or 4, and transargononic with covalence 4, 5, or 6. In some cases the structure is an argononic transargononic hybrid. Fractional bonds (ligancy greater than covalence) are found in some minerals, such as galena.
author_names: Linus Pauling
title: CRYSTALLOGRAPHY AND CHEMICAL BONDING OF SULFIDE MINERALS
year: 2014

abstract: Abstract Thiophosphorous compounds: diisobutyl dithiophosphate (DIBDTPA) diisobutyl dithiophosphinate (DIBDTPI) diisobutyl monothiophosphate (DIBMTPA) and diisobutyl monothiophosphinate (DIBMTPI) are widely used as flotation collectors and corrosion inhibitors, though the true nature of their bonding mechanisms to solid surfaces is still unclear. Using density functional theory (DFT) calculations, this study investigates the structure reactivity relationship of these thiophosphorus molecules as flotation collectors with sulfide minerals. The results indicate that the O atom(s) bonded to the P atom in thiophosphorus molecules can significantly impact the chemical reactivity of the S atom(s) in the four reagents, and for DIBMTPA and DIBMTPI, they could even attend the chemical bond formation with metal atoms. The reactive power of the four compounds to mineral surfaces of Cu, Au, Ag and Pb sulfides is predicted to be DIBDTPI DIBMTPI DIBDTPA DIBMTPA, and their flotation selectivity against pyrite and sphalerite is suggested as DIBDTPA
author_names: Guangyi Liu

Jingjing Xiao

Diwen Zhou

Hong Zhong

Phillip Choi

Zhenghe Xu
title: A DFT study on the structure reactivity relationship of thiophosphorus acids as flotation collectors with sulfide minerals: Implication of surface adsorption
year: 2013

abstract: Simplified electrouic structure models based on molecular orbital calculations are presented for important metal sulfide minerals that contain Zn, Fe and Cu in tetrahedral or triangular coordrnation to sulfur (sphalerite, chalcopyrite, covellite and nukundamite) These "oneEURlectron" MO/ban,d' theory models are correlated with the properties of the minerals. The models correlate well with electrical properties of pure and iron bearing sphalerite and with the hardness and stability variations resulting from iron substitution in sphalerite. The reflectance curves of chalcopyrite and covellite, which relate directly to their distinctive appearance under the reflected light microscope, can be explained by using electronic transitions (both sulfur metal charge transfer transitions and crystalfield transitions) predicted by the models. If data on properties are not available, the models enable some general predictions regarding electrical. oF tical and thermochemical behavior to be made. Keyworils: sulfides, bonding, molecular orbitals, sphalerite, chalcopyrite, covellite.
author_names: David J Vaughan

John A Tossbll
title: THE CHEMICAL BOND AND THE PROPEBTIES OF SULFIDE MINERALS
year: 2007

abstract: The structural diversity of arsenic sulfide molecules in compositions between As4S6 and As4 was investigated using ab initio quantum chemical calculations. The As4S6 molecule consists of four trigonal pyramid coordinations of As atoms bonding to three S atoms. In the As4S5 composition, only one type of molecular configuration corresponds to an uzonite type molecule. In the As4S4 composition, two molecular configurations exist with realgar type and pararealgar type molecules. Three molecular configurations are in the As4S3 composition. The first configuration comprises trigonal pyramidal As atom coordinations of two types: bonding to two S atoms and one As atom, and bonding to one S atom and two As atoms. The second is the molecular configuration of dimorphite. The third comprises trigonal pyramidal As atom coordinations of two types: bonding to three As atoms, and bonding to one As atom and two S atoms. The As4S2 composition allows molecular configurations of two types. One is comprised of trigonal pyramidal As atom configurations of one type bonding to two As atoms and one S atom. The other comprises trigonal pyramidal As atom coordinations of three types: bonding to two S atoms and one As atoms, bonding to one S atom and two As atoms, and bonding to three As atoms. The As4S molecule has trigonal pyramidal As atom coordinations of two types: bonding to one S atom and two As atoms, and bonding to three As atoms. The As4S composition permits only one molecular configuration, which suggests that the mineral duranusite comprises the As4S molecular geometry. In all, ten molecular configurations are predicted in the molecular hierarchy of the arsenic sulfide binary system. The simulated Raman spectral profiles are helpful in searching for undiscovered arsenic sulfide minerals.
author_names: Atsushi Kyono
title: Ab initio quantum chemical investigation of arsenic sulfide molecular diversity from As4S6 and As4
venue: Physics and Chemistry of Minerals
year: 2013

abstract: The sulfide minerals exhibit a rich diversity in sturctural chemistry and in electrical, magnetic and other physical properties. Models based on molecular orbital theory and incorporating some elements of band theory can be developed to describe the diverse valence electron behavior in these minerals. Qualitative models can be proposed on the basis of observed properties, and the models can be tested and refined using experimental data from X ray emission and X ray photoelectron spectroscopy and quantum mechanical calculations performed on cluster units which form the basic building blocks of the crystals.This approach to chemical bonding in sulfide minerals is illustrated for binary non transition metal sulfides (ZnS, CdS, HgS, PbS) binary transition metal sulfides (FeS2, CoS2, NiS2, CuS2 ZnS2) and more complex sulfides (CuFeS2, Cu2S, Ag2S, CuS, Co3S4, CuCo2S4, Fe3S4) The relationship between qualitative and quantitative theories is reviewed with reference to the pyrite marcasite arsenopyrite loellingite series of minerals. Application of the models to understanding structure determining principles, relative stabilities, solid solution limits and properties such as color, reflectance and hardness are discussed.
author_names: David J Vaughan

John A Tossell
title: Electronic structures of sulfide minerals Theory and experiment
year: 1983

abstract: Sulfur is the fifteenth most abundant element in the continental crust of the Earth (260 ppm) and the sixth most abundant element in seawater (885 ppm) Sulfur (atomic number 16) has the ground state electronic structure [Ne]3 s 2 3p 4 and is the first of the group VIB elements in the periodic table (S, Se, Te, Po) In minerals, sulfur can occur in the formal valence states S2 S, S4+ and S6+ corresponding to the sulfide minerals, native sulfur the sulfite minerals, and the sulfate minerals. In the sulfide minerals, S2 functions as a simple anion (e.g. CuFeS2, chalcopyrite) and as a compound S2 anion (e.g. FeS2, pyrite) In the sulfosalts, S2 functions as a component of a complex anion (e.g. AsS3 in tennantite, Cu12As4S13) In the sulfite minerals, S4+ has four valence electrons available for chemical bonding, and occurs in triangular pyramidal coordination with O. In the sulfate minerals, S6+ has six valence electrons available for bonding, and occurs in tetrahedral coordination with O. In addition, there are the thiosulfate minerals, in which S is in the hexavalent state, but is coordinated by three O2 anions and one S2 anion. Chemists frequently write the thiosulfate group as S2O3; however, we write it as SO3S to emphasize that one of the S atoms is an anion and is involved in a tetrahedral group. Although the focus of this chapter is the sulfate minerals, we will deal also with the sulfite and thiosulfate minerals, as they occur in the same types of geochemical environments. We adopt a pragmatic approach to matters involving chemical bonding. We use bond valence theory
author_names: Frank Christopher Hawthorne

Sergey V Krivovichev

Peter C Burns
title: The Crystal Chemistry of Sulfate Minerals
year: 2000

abstract: Copper bearing ore containing talc is generally considered as the most refractory type in various chalcopyrite ores, which is predominantly due to the fact that it includes talc and good natural floatability of talc adversely affects the recovery of chalcopyrite. Flotation is the most economical and effective method to separate copper sulfide minerals and talc. For flotation process, there are selective flotation of talc before flotation of copper bearing minerals, the flotation of copper bearing minerals with depression of talc, and the bulk flotation of talc and copper bearing minerals. At present, the researches focus on the depression of talc. The present work reviewed the molecular structure, properties and mechanism of organic and inorganic depressors for talc. The mechanism of action of depressors for talc includes electrostatic interaction, hydrogen bonding and chemical bonding. At the same time, factors such as pH and ionic strength have an important influence on depression effect for talc. The synergism of combined depressors has various novel depression effects on talc surface, which is more efficient than single agent. In the future, separation technology for talc and chalcopyrite develops toward the application of new depressors and the modification of agents. Meanwhile, the development of new depressors for talc needs to consider the properties of associated minerals with talc and copper bearing minerals. The combined depressors should be developed to maximize the recovery of valuable metals.
author_names: Runpeng Liao

Jiu-shuai Deng

Hao Lai

Jiaozhong Cai

Xi Kuan Zhang

Shuming Wen

Hua Yang

Jianying Deng

Jian Jun Fang

Xuesong Sun
title: An Overview of Technologies and Selective Depressing Agents for Separating Chalcopyrite and Talc
year: 2018

abstract: The metal sulfides exhibit a great diversity of electrical and magnetic properties with both scientific interest and practical applications. These properties apply major constraints on models of the electronic structure (or chemical bonding) in sulfides (Vaughan and Rosso 2006, this volume) The pure and doped synthetic equivalents of certain sulfide minerals have actual or potential applications in the electronics industries (optical devices, photovoltaics, photodiodes and magnetic recording devices) Sulfides are also components of many thin film devices and have been extensively investigated as part of the nanotechnology revolution. Certain electrical and magnetic properties of sulfide minerals mean they contribute to geomagnetism and paleo magnetism, and provide the geophysical prospector with exploration tools for metalliferous ore deposits. To the mineral technologist, these same properties provide methods for the separation of the metal bearing sulfides from associated waste minerals after mining and milling and before extraction of the metal by pyrometallurgical or hydrometallurgical treatment. In this chapter, the theory and measurement of electrical and magnetic properties are outlined along with spectroscopic and diffraction studies that can provide insights into magnetic behavior are discussed. A brief review of electrical and magnetic studies of major sulfide minerals includes some examples of the applications of sulfide electrical and magnetic properties, including special consideration of the properties of sulfide nanoparticles. Most of the available data presented are for pure synthetic binary and ternary sulfides, as very small concentrations of impurities can dramatically affect electrical properties leading to problems of interpreting data from natural samples. Although data for several of the commonly found sulfides are discussed in this chapter, no attempt is made at a comprehensive coverage. The section below on theory and measurement of electrical and magnetic properties draws on the account given in Vaughan and Craig (1978) to which readers are referred for further details. It
author_names: Carolyn I Pearce

Richard AD Pattrick

David J Vaughan
title: Electrical and magnetic properties of sulfides
year: 2006