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mscic能给我们这些没用过G4的虫子扫扫盲么？
以下是自己搜的关于G4的介绍，贴出来跟大家一起学习：
Gaussian-4 (G4) Theory
Gaussian-4 theory1 is the fourth in a series of Gx methods for calculation of molecular energies. It is a composite technique in which a sequence of well-defined ab initio molecular orbital calculations is performed to arrive at a total energy of a given molecular species. Geometries are determined using B3LYP density functional theory with the 6-31G(2df,p) basis set [6-31G(2fg) for third-row nontransition metal elements). Zero-point energies are also calculated with this basis set. Correlation level calculations are done using Moller-Plesset perturbation theory up to fourth-order and with coupled cluster theory. Large basis sets, including multiple sets of polarization functions, are used in the correlation calculations. Three basis sets that are used in G4 theory are available on this web site. These are the G3LargeXP basis used in the MP2(FU) step and two basis sets (quadrupole-zeta and quintuple-zeta) used for extrapolation to the Hartree-Fock limit. The latter two are derived from correlation consistent basis sets.
The G4 theory has been assessed on the G3/05 test set2. It has 454 energies including enthalpies of formation, ionization potentials, electron affinities, proton affinities, and hydrogen bond energies. The comprehensive set includes the energies in the original G2 test set, the G2/97 test set, and the G3/99 test set. contains 302 entries.
Basis sets for single point energy calculations: G3LargeXP, HFQZ, HF5Z
Basis set for K,Ca,Ga-Kr for B3LYP geometry optimizations: 6-31G(2fg)
G5/03 test set: G4 total energies
G5/03 test set: G4 deviations with experiment
[ Last edited by xiaowandouer on 2010-12-31 at 11:41 ] |
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