molecular electronic structureorbital calculation methodsquantum theory applications/ energy localisationgroup theorycontinuous degeneracydegenerate orbitalssymmetry groupsThe energy-localization method is examined for continuous degeneracy using a grouptheoretic approach. Conditions for the degenerate orbitals are ...
The EDA utilizes absolutely localized molecular orbitals to define intermediate states and is compatible with excited state methods based on linear response theory such as configuration interaction singles and time-dependent density functional theory. The shift in excitation energy when an excited molecule ...
MOLECULARORBITALPROBLEMS1.Amolecularorbital(MO)energyleveldiagramappropriateforhomonucleardiatomicmoleculesfromLi2toN2isshownbelow.Answerthefollowingwithreference,whenappropriate,tothediagram.Assumezistheinternuclearaxis.2.a.Brieflyexplainwhatismeantbythestatement"molecularorbitalsareformedbythelinearcombinationofatomicorbi...
Overview of the quantum computed moments (QCM) approach applied to problems in chemistry. (a) The molecular system H6 is represented by a second-quantised Hamiltonian over a set of molecular orbitals. The trial-state is the Hartree–Fock state, i.e. the occupation of the indicated orbitals. ...
Rydberg atoms, with their enormous electronic orbitals, exhibit dipole–dipole interactions reaching the gigahertz range at a distance of a micrometre, making them a prominent contender for realizing ultrafast quantum operations. However, such strong interactions between two single atoms have so far never...
A qualitative interpretation of the Kohn–Sham highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) orbitals is given based on the present calculations. 1997 John Wiley & Sons, Inc. Int J Quant Chem 65: 749–758, 1997 展开 ...
A careful optimization of the molecular orbitals in a multiconfiguration self-consistent-field (MCSCF) procedure turns out to be crucial for the reliability of the ACPF and MRSDCI energy derivatives. If the orbitals are not consistent with the electron correlation treatment the gradient corrections ...
“Hamiltonian” is a quantum mechanical energy operator that describes the interactions between all the electron orbitals and nuclei of the constituent atoms. The “lowest energy” state of the molecular Hamiltonian dictates the structure of the molecule and how it will interact with other molecules....
Electronegativities and the bonding character of molecular orbitals: A remark From the density functional theory of Hohenberg-Kohn it is possible to prove that a molecular orbital is bonding (antibonding) if its electronegativity is ... AOD Amorim,R Ferreira - 《Theoretica Chimica Acta》 被引量:...
Divide-Expand-Consolidate (DEC) is a local correlation method where the inherent locality of the electron correlation problem is used to express the correlated calculation on a large molecular system in terms of small independent fragment calculations employing small subsets of local HF orbitals. A cr...