scholarly journals Reduced-Scaling Correlation Methods for the Excited States of Large Molecules: Implementation and Benchmarks for the Second-Order Algebraic-Diagrammatic Construction Approach

2019 ◽  
Vol 15 (11) ◽  
pp. 6111-6126 ◽  
Author(s):  
Dávid Mester ◽  
Péter R. Nagy ◽  
Mihály Kállay
Keyword(s):  
Excited States ◽  
Second Order ◽  
Large Molecules ◽  
Correlation Methods ◽  
Order Algebraic

scholarly journals Accuracy of Spin-Component Scaled ADC(2) Excitation Energies and Potential Energy Surfaces

2019 ◽  
Author(s):  
Attila Tajti ◽  
Levente Tulipan ◽  
Péter Szalay
Keyword(s):  
Potential Energy ◽  
Excited States ◽  
Canonical Form ◽  
Potential Energy Surfaces ◽  
Second Order ◽  
Spin Component ◽  
Excitation Energies ◽  
Order Algebraic ◽  
Energy Surfaces

In a recent paper of this Journal (Tajti and Szalay, JCTC 2019, 15, 5523) we have shown that failures of the CC2 method to describe Rydberg excited states, as well as potential energy surfaces of certain valence excited states can be cured by spin-component scaled (SCS) versions SCS-CC2 and SOS-CC2 by a large extent. In this paper, the related and popular Second Order Algebraic Diagrammatic Construction (ADC(2)) method and its SCS variants are inspected with the previously established methodology. The results reflect the similarity of the CC2 and ADC(2) models, showing identical problems in the case of the canonical form and the same improvement when spin-component-scaling is applied.

scholarly journals Accuracy of Spin-Component Scaled ADC(2) Excitation Energies and Potential Energy Surfaces

2019 ◽  
Author(s):  
Attila Tajti ◽  
Levente Tulipan ◽  
Péter Szalay
Keyword(s):  
Potential Energy ◽  
Excited States ◽  
Canonical Form ◽  
Potential Energy Surfaces ◽  
Second Order ◽  
Spin Component ◽  
Excitation Energies ◽  
Order Algebraic ◽  
Energy Surfaces

In a recent paper of this Journal (Tajti and Szalay, JCTC 2019, 15, 5523) we have shown that failures of the CC2 method to describe Rydberg excited states, as well as potential energy surfaces of certain valence excited states can be cured by spin-component scaled (SCS) versions SCS-CC2 and SOS-CC2 by a large extent. In this paper, the related and popular Second Order Algebraic Diagrammatic Construction (ADC(2)) method and its SCS variants are inspected with the previously established methodology. The results reflect the similarity of the CC2 and ADC(2) models, showing identical problems in the case of the canonical form and the same improvement when spin-component-scaling is applied.

QUANTUM REFLECTION, EVAPORATION, AND TRANSPORT CURRENTS AT 4He SURFACES

2006 ◽  
Vol 20 (30n31) ◽  
pp. 5047-5056
Author(s):  
V. APAJA ◽  
E. KROTSCHECK ◽  
A. RIMNAC ◽  
R. E. ZILLICH
Keyword(s):  
Excited States ◽  
Theoretical Study ◽  
Transport Phenomena ◽  
Microscopic Theory ◽  
Second Order ◽  
Quantum Liquid ◽  
Quantum Reflection ◽  
Quantum Liquids ◽  
Inhomogeneous Quantum

In this work, we study transport currents in excited states. This requires the calculation of particle currents [Formula: see text] to second order in the excitation amplitudes. For that purpose, we take a well-tested microscopic theory of inhomogeneous quantum liquids and extend it to find the mass currents created when atoms scatter off a surface or when excitations evaporate atoms. This is the first theoretical study of transport phenomena in a quantum liquid based on a quantitative microscopic theory.

Sign in / Sign up

Export Citation Format

Share Document