TY - JOUR
T1 - The Fock space coupled cluster method
T2 - theory and application
AU - Kaldor, Uzi
PY - 1991/11
Y1 - 1991/11
N2 - The Fock space coupled cluster method and its application to atomic and molecular systems are described. The importance of conserving size extensivity is demonstrated by the electron affinities of the alkali atoms. Two types of intruder states are discussed, one attributable to the orbital energy spectrum and the other caused by two-electron interactions. They are illustrated by the excited states of Li2 and by1S states of Be, respectively. It is shown how both problems may be solved using incomplete model spaces. The selection of the model space in a moderately dense spectrum is discussed in connection with N2 excited states.
AB - The Fock space coupled cluster method and its application to atomic and molecular systems are described. The importance of conserving size extensivity is demonstrated by the electron affinities of the alkali atoms. Two types of intruder states are discussed, one attributable to the orbital energy spectrum and the other caused by two-electron interactions. They are illustrated by the excited states of Li2 and by1S states of Be, respectively. It is shown how both problems may be solved using incomplete model spaces. The selection of the model space in a moderately dense spectrum is discussed in connection with N2 excited states.
KW - Coupled cluster method
KW - Electronic transition energies
KW - Incomplete model spaces
KW - Intruder states
UR - http://www.scopus.com/inward/record.url?scp=33646852587&partnerID=8YFLogxK
U2 - 10.1007/BF01119664
DO - 10.1007/BF01119664
M3 - ???researchoutput.researchoutputtypes.contributiontojournal.article???
AN - SCOPUS:33646852587
VL - 80
SP - 427
EP - 439
JO - Theoretical Chemistry Accounts
JF - Theoretical Chemistry Accounts
SN - 1432-881X
IS - 6
ER -