Geminals as wavefunction building blocks: new level of model chemistries

Description

Geminals as wavefunction building blocks: new level of model chemistries Vitaly A. Rassolov, with Feng Xu Department of Chemistry and Biochemistry, University of South Carolina, Columbia, SC 29208 Thanks to Peter Surjan, Agnes Szabados, Sophya Garashchuk, NSF, PRF

• all calculation


• amplitudes then either


• model chemistry


• single determinant


• polyno- mial scaling


• spin treatment


• reference wavefunction


• better analysis


• theoretical model


• leading perturbative

Sujets

• Szabados
• Surjan
• Theory

Informations

• Publié par: pefav
• Nombre de lectures: 15
• Langue: English

Extrait

Geminalsaswavefunctionbuilding blocks:newlevelofmodelchemistries VitalyA.Rassolov,withFengXu DepartmentofChemistryandBiochemistry,UniversityofSouthCarolina, Columbia,SC29208 hTnaskotePetruSr ´ , ka´j,ngAenszSbaa NSF,PRF od,soShpayaGarhshcu

Guidingprinciples 1.Allknownsizeconsistentmodelchemistriesarebasedonsingledetermi- nantwavefunction •Size-consistent:Energyisarigorouslyextensiveproperty •Modelchemistry:Widelyapplicabletheoreticalmodelfreefromspe- cificadjustableparameters 2.Problems: •Non-dynamiccorrelation:Singledeterminantissometimesqualita- tivelydeficient •Dynamiccorrelation:Slowconvergenceofcorrelationexpansion –“Deadwood”configurationsofFCI –Searchforoptimalsingledeterminant(i.e.Bruecknerorbitals) 3.Electronpair(or“geminal”)isanaturalbuildingblockinchemistry •Physicallybetterreferencewavefunction •Betteranalysisofperturbativecorrections