Self-consistent calculation of total energies of the electron gas using many-body perturbation theory

Calculation of Dissociation Energies Using Many - Body Perturbation Theory

A major task for theoretical chemists is the development of methods to predict energy differences with chemical accuracy. Most quantum chemists agree that accurate prediction of relative energies requires application of theories that include electron correlation effects, effects not treated in self-consistent-field (SCF) calculations [1-4]. Estimates of molecular correlation energy have been ob...

Calculation of Exchange Energies Using Algebraic Perturbation Theory

hazard evaluation of gas condensate stabilization and dehydration unit of parsian gas refinery using hazop procedures

شناسایی مخاطرات در واحد 400 پالایشگاه گاز پارسیان. در این پروزه با بکارگیری از تکنیک hazop به شناسا یی مخاطرات ، انحرافات ممکن و در صورت لزوم ارایه راهکارهای مناسب جهت افزایش ایمنی فرا یند پرداخته میگردد. شرایط عملیاتی مخاطره آمیز نظیر فشار و دمای بالا و وجود ترکیبات مختلف سمی و قابل انفجار در واحدهای پالایش گاز، ضرورت توجه به موارد ایمنی در این چنین واحدهایی را مشخص می سازد. مطالعه hazop یک ر...

Accuracy and limitations of second-order many-body perturbation theory for predicting vertical detachment energies of solvated-electron clusters.

Vertical electron detachment energies (VDEs) are calculated for a variety of (H(2)O)(n)(-) and (HF)(n)(-) isomers, using different electronic structure methodologies but focusing in particular on a comparison between second-order Møller-Plesset perturbation theory (MP2) and coupled-cluster theory with noniterative triples, CCSD(T). For the surface-bound electrons that characterize small (H(2)O)...

Development of Many-Body Perturbation Theory

The development of standard MBPT for single-reference and multi-reference cases is reviewed, and its extension to the relativistic case in the form of the Dirac-Coulomb-Breit (DCB) approximation is described. The latter scheme is non-covariant, and the recent development of a fully covariant MBPT scheme is discussed. This is based upon a new scheme for quantumelectrodynamical (QED) calculations...