On the Pb-Pd system. Calorimetric studies and ab-initio aided thermodynamic calculations

Ab initio MP2/6-311++G(d,p) structure optimizations and frequency calculations have been carried out on 10 polymers, (HX)n; on eight polyhalohydrogenate(1-) anions, HnXn+1-, and on four polyhalohydrogen(I) cations, Hn+1Xn+, (X = F and Cl) at a number of temperatures from 188 to 673 K, and at various total pressures. From the results, ΔG° and K values have been calculated for some reactions involving these species, and the relative amounts determined under a variety of conditions: nHX –> (HX)n (n = 2-6) HX + HnXn+1- àHn+1Xn+2- (n = 0-3) HX + Hn+1Xn+ àHn+2Xn+1+ (n = 0, 1) There are some marked differences between the fluorine and chlorine series, but generally, the relative amounts of the large molecules and ions decrease as the temperature increases. For all reactions, ln K can be expressed as function to the fourth power in 1/T indicating that ΔH° is more or less temperature dependent over a range of 400-500°.Key words: ab initio, thermodynamics, HCl, HF.

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Prediction of high-temperature point defect formation in TiO2 from combined ab initio and thermodynamic calculations

Acta Materialia ◽

10.1016/j.actamat.2007.04.005 ◽

2007 ◽

Vol 55 (13) ◽

pp. 4325-4337 ◽

Cited By ~ 95

Author(s):

J. He ◽

R.K. Behera ◽

M.W. Finnis ◽

X. Li ◽

E.C. Dickey ◽

...

Keyword(s):

High Temperature ◽

Ab Initio ◽

Point Defect ◽

Defect Formation ◽

Thermodynamic Calculations

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Calorimetric studies and thermodynamic calculations of the Ag-Mg system

Journal of Alloys and Compounds ◽

10.1016/j.jallcom.2021.161937 ◽

2021 ◽

pp. 161937

Author(s):

A. Dębski ◽

W. Gierlotka ◽

W. Gąsior

Keyword(s):

Thermodynamic Calculations ◽

Calorimetric Studies

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Theoretical study on tetrazole and its derivatives. Part 7: ab initio MO and thermodynamic calculations on azido derivatives of tetrazole

Journal of Molecular Structure THEOCHEM ◽

10.1016/s0166-1280(98)00249-8 ◽

1999 ◽

Vol 458 (3) ◽

pp. 249-256 ◽

Cited By ~ 18

Author(s):

Chen Zhaoxu ◽

Fan Jianfen ◽

Xiao Heming

Keyword(s):

Ab Initio ◽

Theoretical Study ◽

Thermodynamic Calculations ◽

Ab Initio Mo ◽

Derivatives Of

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Ab-initio thermodynamic calculations of Mg2BIV (BIV = Si, Ge, Sn) solid solutions

physica status solidi (RRL) - Rapid Research Letters ◽

10.1002/pssr.200701299 ◽

2008 ◽

Vol 2 (2) ◽

pp. 56-58 ◽

Cited By ~ 6

Author(s):

Q. Zhang ◽

X. B. Zhao ◽

T. J. Zhu ◽

J. P. Tu

Keyword(s):

Ab Initio ◽

Solid Solutions ◽

Thermodynamic Calculations

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Stability of Ti–B–N solid solutions and the formation of nc-TiN/a-BN nanocomposites studied by combined ab initio and thermodynamic calculations

Acta Materialia ◽

10.1016/j.actamat.2008.04.066 ◽

2008 ◽

Vol 56 (16) ◽

pp. 4440-4449 ◽

Cited By ~ 28

Author(s):

R.F. Zhang ◽

S.H. Sheng ◽

S. Veprek

Keyword(s):

Ab Initio ◽

Solid Solutions ◽

Thermodynamic Calculations

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Ab initio band theory approach to electron energy loss near edge structures

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100104595 ◽

1988 ◽

Vol 46 ◽

pp. 506-507

Author(s):

Xudong Weng ◽

O.F. Sankey ◽

Peter Rez

Keyword(s):

Ab Initio ◽

Local Density ◽

Interpolation Method ◽

Atomic Orbital ◽

Plane Waves ◽

Large Set ◽

Theory Approach ◽

Band Theory ◽

Atomic Orbitals ◽

Pseudopotential Calculations

Single electron band structure techniques have been applied successfully to the interpretation of the near edge structures of metals and other materials. Among various band theories, the linear combination of atomic orbital (LCAO) method is especially simple and interpretable. The commonly used empirical LCAO method is mainly an interpolation method, where the energies and wave functions of atomic orbitals are adjusted in order to fit experimental or more accurately determined electron states. To achieve better accuracy, the size of calculation has to be expanded, for example, to include excited states and more-distant-neighboring atoms. This tends to sacrifice the simplicity and interpretability of the method.In this paper. we adopt an ab initio scheme which incorporates the conceptual advantage of the LCAO method with the accuracy of ab initio pseudopotential calculations. The so called pscudo-atomic-orbitals (PAO's), computed from a free atom within the local-density approximation and the pseudopotential approximation, are used as the basis of expansion, replacing the usually very large set of plane waves in the conventional pseudopotential method. These PAO's however, do not consist of a rigorously complete set of orthonormal states.

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