Description
This keyword requests a general Complete Basis Set extrapolation of the MP2 energy [ Nyden81 M. R. Nyden and G. A. Petersson, “Complete basis set correlation energies. I. The asymptotic convergence of pair natural orbital expansions,” J. Chem. Phys., 75 (1981) 1843-62. DOI: , Petersson88 G. A. Petersson, A. Bennett, T. G. Tensfeldt, M. A. Al-Laham, W. A. Shirley, and J. Mantzaris, “A complete basis set model chemistry. I. The total energies of closed-shell atoms and hydrides of the first-row atoms,” J. Chem. Phys., 89 (1988) 2193-218. DOI: , Petersson91 G. A. Petersson and M. A. Al-Laham, “A complete basis set model chemistry. II. Open-shell systems and the total energies of the first-row atoms,” J. Chem. Phys., 94 (1991) 6081-90. DOI: , Petersson91a G. A. Petersson, T. G. Tensfeldt, and J. A. Montgomery Jr., “A complete basis set model chemistry. III. The complete basis set-quadratic configuration interaction family of methods,” J. Chem. Phys., 94 (1991) 6091-101. DOI: ].
The method requires two parameters: the minimum number of pair natural orbitals and the integration grid, which are set with the CBSExtrapolate=NMin and Integral=Grid options, respectively.
The minimum number of pair natural orbitals defaults to 5 for the 6-31G**, 6-31G‡ and 6-311G** basis sets (with or without diffuse functions), and to 10 for the 6-311G basis set with (2df,p) or (3df,p) polarization functions (again, with or without diffuse functions). NMin must be specified in all other cases, or an error will result.
The default integration grid is the (99,590) grid; an alternate grid can be specified with the Integral=Grid keyword. The integration portion is a small part of the total CBS extrapolation computation, so this relatively large grid was chosen. See the description of the Integral keyword for a full discussion of the available grids.
入力
Options
NMin=N
Specifies N as the minimum number of pair natural orbitals.
MinPopLocal
Use localization based on populations in minimal basis [ Montgomery00 J. A. Montgomery Jr., M. J. Frisch, J. W. Ochterski, and G. A. Petersson, “A complete basis set model chemistry. VII. Use of the minimum population localization method,” J. Chem. Phys., 112 (2000) 6532-42. DOI: ]. This is the default.
PopLocal
Use population localization as described in reference [ Pipek89 J. Pipek and P. G. Mezey, “A fast intrinsic localization procedure applicable for ab initio and semiempirical linear combination of atomic orbital wave functions,” J. Chem. Phys., 90 (1989) 4916-26. DOI: ].
BoysLocal
Use Boys localization [ Boys60 S. F. Boys, “Construction of Molecular Orbitals to be Approximately Invariant for Changes from One Molecule to Another,” Rev. Mod. Phys., 32 (1960) 296-99. DOI: , Foster60 J. M. Foster and S. F. Boys, “Canonical configurational interaction procedure,” Rev. Mod. Phys., 32 (1960) 300-02. DOI: , Boys66].
NoLocal
Do not use any localization.
NRPopLocal
Newton-Raphson population localization.
NRBoysLocal
Newton-Raphson Boys localization.
NRMinPopLocal
Use 2nd order minimal population analysis.
SaveOrbitals
Save the localized CBS orbitals to the read-write file. Note that they will replace the SCF orbitals.
オプション
Availability
Single point energy calculations only, using any electron correlation method.
関連キーワード
This keyword requests a general Complete Basis Set extrapolation of the MP2 energy [ Nyden81 M. R. Nyden and G. A. Petersson, “Complete basis set correlation energies. I. The asymptotic convergence of pair natural orbital expansions,” J. Chem. Phys., 75 (1981) 1843-62. DOI: , Petersson88 G. A. Petersson, A. Bennett, T. G. Tensfeldt, M. A. Al-Laham, W. A. Shirley, and J. Mantzaris, “A complete basis set model chemistry. I. The total energies of closed-shell atoms and hydrides of the first-row atoms,” J. Chem. Phys., 89 (1988) 2193-218. DOI: , Petersson91 G. A. Petersson and M. A. Al-Laham, “A complete basis set model chemistry. II. Open-shell systems and the total energies of the first-row atoms,” J. Chem. Phys., 94 (1991) 6081-90. DOI: , Petersson91a G. A. Petersson, T. G. Tensfeldt, and J. A. Montgomery Jr., “A complete basis set model chemistry. III. The complete basis set-quadratic configuration interaction family of methods,” J. Chem. Phys., 94 (1991) 6091-101. DOI: ].
The method requires two parameters: the minimum number of pair natural orbitals and the integration grid, which are set with the CBSExtrapolate=NMin and Integral=Grid options, respectively.
The minimum number of pair natural orbitals defaults to 5 for the 6-31G**, 6-31G‡ and 6-311G** basis sets (with or without diffuse functions), and to 10 for the 6-311G basis set with (2df,p) or (3df,p) polarization functions (again, with or without diffuse functions). NMin must be specified in all other cases, or an error will result.
The default integration grid is the (99,590) grid; an alternate grid can be specified with the Integral=Grid keyword. The integration portion is a small part of the total CBS extrapolation computation, so this relatively large grid was chosen. See the description of the Integral keyword for a full discussion of the available grids.
実例
NMin=N
Specifies N as the minimum number of pair natural orbitals.
MinPopLocal
Use localization based on populations in minimal basis [ Montgomery00 J. A. Montgomery Jr., M. J. Frisch, J. W. Ochterski, and G. A. Petersson, “A complete basis set model chemistry. VII. Use of the minimum population localization method,” J. Chem. Phys., 112 (2000) 6532-42. DOI: ]. This is the default.
PopLocal
Use population localization as described in reference [ Pipek89 J. Pipek and P. G. Mezey, “A fast intrinsic localization procedure applicable for ab initio and semiempirical linear combination of atomic orbital wave functions,” J. Chem. Phys., 90 (1989) 4916-26. DOI: ].
BoysLocal
Use Boys localization [ Boys60 S. F. Boys, “Construction of Molecular Orbitals to be Approximately Invariant for Changes from One Molecule to Another,” Rev. Mod. Phys., 32 (1960) 296-99. DOI: , Foster60 J. M. Foster and S. F. Boys, “Canonical configurational interaction procedure,” Rev. Mod. Phys., 32 (1960) 300-02. DOI: , Boys66].
NoLocal
Do not use any localization.
NRPopLocal
Newton-Raphson population localization.
NRBoysLocal
Newton-Raphson Boys localization.
NRMinPopLocal
Use 2nd order minimal population analysis.
SaveOrbitals
Save the localized CBS orbitals to the read-write file. Note that they will replace the SCF orbitals.