Matches in SemOpenAlex for { <https://semopenalex.org/work/W2043289049> ?p ?o ?g. }
- W2043289049 endingPage "230" @default.
- W2043289049 startingPage "217" @default.
- W2043289049 abstract "Abstract Several variants of coupled electron pair type approximations are compared with respect to their accuracy in the prediction of bond distances, harmonic vibrational frequencies and anharmonic corrections for a range of closed-shell diatomic molecules. In the first part of the paper the coupled-electron pair (CEPA) methods (CEPA/1,2,3) are discussed. Extensions of these methods allow the derivation of the correlation energy from the stationarization of a correlation energy functional (CPF/1,2,3 methods). All methods are formulated as diagonally dressed configuration–interaction with single- and double-excitations (CISD) eigenvalue problems. Averaging the diagonal shifts of the CPF methods in various ways lead to the ACPF and AQCC methods. Several small modifications of the shifts for the single excitations are proposed that enhance the stability of the methods (NCPF/1,2,3, NCEPA/1,2,3, NACPF). The reduced shifts are justified by linear response arguments. The implementation of the methods for a closed-shell ground state is described. In the application part, we first tested the size-consistency, exactness for two-electron systems and unitary invariance of the methods. Extensive numerical studies with polarized quadruple-ζ basis sets are employed to test the accuracy of the coupled pair approaches relative to the more elaborate quadratic CI (QCISD) and coupled-cluster (CCSD and CCSD(T)) approaches. Not surprisingly, the CCSD(T) method is the most accurate approach on average. However, the proposed NCPF/1 variant led to even smaller average errors for bond distances (∼0.2 pm relative to ∼0.3 pm for CCSD(T)) while predicting still accurate harmonic frequencies (av. Error ∼25 cm−1 for NCPF/1, ∼8 cm−1 for CCSD(T) and ∼45 cm−1 for CCSD). All coupled pair methods are more accurate than present day DFT approaches (BP86, B3LYP). The exception is the recently proposed double-hybrid B2PLYP functional that approaches the coupled pair performance. Some more difficult copper containing diatomics are treated as well (CuH, CuF, CuCl and Cu2). We discuss why we believe that the coupled-pair approaches (and in particular the proposed NCPF/1 variant) are attractive for large-scale chemical applications." @default.
- W2043289049 created "2016-06-24" @default.
- W2043289049 creator A5003872223 @default.
- W2043289049 creator A5046820685 @default.
- W2043289049 date "2008-01-01" @default.
- W2043289049 modified "2023-09-27" @default.
- W2043289049 title "A comparative study of single reference correlation methods of the coupled-pair type" @default.
- W2043289049 cites W135867663 @default.
- W2043289049 cites W1487133985 @default.
- W2043289049 cites W1521857819 @default.
- W2043289049 cites W1584675441 @default.
- W2043289049 cites W1596002078 @default.
- W2043289049 cites W1953850726 @default.
- W2043289049 cites W1964433176 @default.
- W2043289049 cites W1964514063 @default.
- W2043289049 cites W1964577547 @default.
- W2043289049 cites W1965999814 @default.
- W2043289049 cites W1969625288 @default.
- W2043289049 cites W1971861013 @default.
- W2043289049 cites W1972347699 @default.
- W2043289049 cites W1973074894 @default.
- W2043289049 cites W1975109687 @default.
- W2043289049 cites W1978849007 @default.
- W2043289049 cites W1979206729 @default.
- W2043289049 cites W1979259297 @default.
- W2043289049 cites W1980667009 @default.
- W2043289049 cites W1982101094 @default.
- W2043289049 cites W1982356449 @default.
- W2043289049 cites W1983010725 @default.
- W2043289049 cites W1983331399 @default.
- W2043289049 cites W1983809391 @default.
- W2043289049 cites W1983903086 @default.
- W2043289049 cites W1985502232 @default.
- W2043289049 cites W1986055213 @default.
- W2043289049 cites W1987547360 @default.
- W2043289049 cites W1990790376 @default.
- W2043289049 cites W1995014289 @default.
- W2043289049 cites W1995326709 @default.
- W2043289049 cites W1995792670 @default.
- W2043289049 cites W1997238448 @default.
- W2043289049 cites W1998705691 @default.
- W2043289049 cites W1999338148 @default.
- W2043289049 cites W1999440372 @default.
- W2043289049 cites W1999758065 @default.
- W2043289049 cites W2000660719 @default.
- W2043289049 cites W2009848407 @default.
- W2043289049 cites W2010558348 @default.
- W2043289049 cites W2010721993 @default.
- W2043289049 cites W2010764571 @default.
- W2043289049 cites W2011321799 @default.
- W2043289049 cites W2014015984 @default.
- W2043289049 cites W2014592066 @default.
- W2043289049 cites W2015195977 @default.
- W2043289049 cites W2015419938 @default.
- W2043289049 cites W2015701404 @default.
- W2043289049 cites W2015797016 @default.
- W2043289049 cites W2016834143 @default.
- W2043289049 cites W2018217082 @default.
- W2043289049 cites W2021507329 @default.
- W2043289049 cites W2023006311 @default.
- W2043289049 cites W2023271753 @default.
- W2043289049 cites W2028068895 @default.
- W2043289049 cites W2030687437 @default.
- W2043289049 cites W2031856796 @default.
- W2043289049 cites W2036118309 @default.
- W2043289049 cites W2037928467 @default.
- W2043289049 cites W2039664517 @default.
- W2043289049 cites W2040134477 @default.
- W2043289049 cites W2040496996 @default.
- W2043289049 cites W2041325516 @default.
- W2043289049 cites W2044591029 @default.
- W2043289049 cites W2045403544 @default.
- W2043289049 cites W2047072197 @default.
- W2043289049 cites W2049303112 @default.
- W2043289049 cites W2050177505 @default.
- W2043289049 cites W2051299760 @default.
- W2043289049 cites W2058210956 @default.
- W2043289049 cites W2058264039 @default.
- W2043289049 cites W2060858284 @default.
- W2043289049 cites W2067499387 @default.
- W2043289049 cites W2070203126 @default.
- W2043289049 cites W2070708006 @default.
- W2043289049 cites W2075486066 @default.
- W2043289049 cites W2078770559 @default.
- W2043289049 cites W2080942482 @default.
- W2043289049 cites W2082037815 @default.
- W2043289049 cites W2082685920 @default.
- W2043289049 cites W2082921852 @default.
- W2043289049 cites W2084665482 @default.
- W2043289049 cites W2084869362 @default.
- W2043289049 cites W2085137602 @default.
- W2043289049 cites W2086957099 @default.
- W2043289049 cites W2088108127 @default.
- W2043289049 cites W2088779490 @default.
- W2043289049 cites W2089363127 @default.
- W2043289049 cites W2090658338 @default.
- W2043289049 cites W2090912545 @default.
- W2043289049 cites W2091825943 @default.