Atomistic Simulation of Mineral Surfaces and Interfaces

Computational chemistry is another branch of chemistry that can be used to model the material which is based on the mathematical methods and combined that with the theories of the quantum mechanics. However, in this filed there are two different techniques or categories, classical interatomic potential and the electronic structure methodology. The aim of this paper is to describe how can modelling the structures and energetics of surface and interface processes of minerals surface, using the classical atomistic simulation methods. We will illustrate the types of potentials and some of Codes (Gulp and METADISE) which is needed to do these calculations to elucidate the structures and stabilities as well.

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Atomistic simulation of mineral surfaces: Studies of surface stability and growth

Phase Transitions ◽

10.1080/01411599708223731 ◽

1997 ◽

Vol 61 (1-4) ◽

pp. 83-107 ◽

Cited By ~ 19

Author(s):

S. C. Parker ◽

P. M. Oliver ◽

N.H. De Leeuw ◽

J.O. Titiloye ◽

G. W. Watson

Keyword(s):

Atomistic Simulation ◽

Mineral Surfaces ◽

Surface Stability

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Atomistic simulation of dislocations, surfaces and interfaces in MgO

Journal of the Chemical Society Faraday Transactions ◽

10.1039/ft9969200433 ◽

1996 ◽

Vol 92 (3) ◽

pp. 433 ◽

Cited By ~ 321

Author(s):

Graeme W. Watson ◽

E. Toby Kelsey ◽

Nora H. de Leeuw ◽

Duncan J. Harris ◽

Stephen C. Parker

Keyword(s):

Atomistic Simulation ◽

Surfaces And Interfaces

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Scanning Electron Microscope Study of Bacteria on Mineral Surfaces

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100090634 ◽

1976 ◽

Vol 34 ◽

pp. 130-131

Author(s):

V.K. Berry

Keyword(s):

Oxidation Reaction ◽

Electron Microscope Study ◽

Elemental Sulfur ◽

Thiobacillus Ferrooxidans ◽

Physical Contact ◽

Metal Sulfides ◽

Low Grade ◽

Mineral Surfaces ◽

Mineral Surface ◽

Scanning Electron Microscope Study

There are two strains of bacteria viz. Thiobacillus thiooxidansand Thiobacillus ferrooxidanswidely mentioned to play an important role in the leaching process of low-grade ores. Another strain used in this study is a thermophile and is designated Caldariella .These microorganisms are acidophilic chemosynthetic aerobic autotrophs and are capable of oxidizing many metal sulfides and elemental sulfur to sulfates and Fe2+ to Fe3+. The necessity of physical contact or attachment by bacteria to mineral surfaces during oxidation reaction has not been fairly established so far. Temple and Koehler reported that during oxidation of marcasite T. thiooxidanswere found concentrated on mineral surface. Schaeffer, et al. demonstrated that physical contact or attachment is essential for oxidation of sulfur.

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Inelastic scattering at surfaces and interfaces

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100143560 ◽

1986 ◽

Vol 44 ◽

pp. 392-393

Author(s):

R. H. Ritchie ◽

A. Howie

Keyword(s):

Inelastic Scattering ◽

Surface Properties ◽

Correlation Energy ◽

Condensed Matter ◽

Charged Particles ◽

Condensed Matter Physics ◽

Optical Phonons ◽

Exchange Correlation ◽

Surfaces And Interfaces ◽

Inelastic Interactions

An important part of condensed matter physics in recent years has involved detailed study of inelastic interactions between swift electrons and condensed matter surfaces. Here we will review some aspects of such interactions.Surface excitations have long been recognized as dominant in determining the exchange-correlation energy of charged particles outside the surface. Properties of surface and bulk polaritons, plasmons and optical phonons in plane-bounded and spherical systems will be discussed from the viewpoint of semiclassical and quantal dielectric theory. Plasmons at interfaces between dissimilar dielectrics and in superlattice configurations will also be considered.

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Ultramicrotomy as a Technique for Materials Specimen Preparation

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100135745 ◽

1990 ◽

Vol 48 (2) ◽

pp. 428-429

Author(s):

S.R. Glanvill

Keyword(s):

Materials Science ◽

Structural Information ◽

Specimen Preparation ◽

Preparation Technique ◽

Cross Sectional ◽

Surfaces And Interfaces ◽

Beam Analysis ◽

Flat Embedding ◽

20 Nm ◽

Sectional Analysis

This paper summarizes the application of ultramicrotomy as a specimen preparation technique for some of the Materials Science applications encountered over the past two years. Specimens 20 nm thick by hundreds of μm lateral dimension are readily prepared for electron beam analysis. Materials examined include metals, plastics, ceramics, superconductors, glassy carbons and semiconductors. We have obtain chemical and structural information from these materials using HRTEM, CBED, EDX and EELS analysis. This technique has enabled cross-sectional analysis of surfaces and interfaces of engineering materials and solid state electronic devices, as well as interdiffusion studies across adjacent layers.Samples are embedded in flat embedding moulds with Epon 812 epoxy resin / Methyl Nadic Anhydride mixture, using DY064 accelerator to promote the reaction. The embedded material is vacuum processed to remove trapped air bubbles, thereby improving the strength and sectioning qualities of the cured block. The resin mixture is cured at 60 °C for a period of 80 hr and left to equilibrate at room temperature.

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