MINI basis sets

MIDI—i Same primitives as the MINI basis sets with two contractions to describe the valence orbitals for greater flexibility. 

The application of the LMBPT on the ab initio level to some normal saturated hydrocarbons was first performed using STO-3G basis set (Kapuy et al., 1987). Similar calculations have been carried out by the use of MINI basis set. The transferability of some correlation energy contributions in systems CHa, CsH 2 and CiHie,... 

The ab initio method reproducing correctly compounds based on sp-elements, has been chosen for the simulation of LiF and Si02 in the MINI basis set [6], allowing relatively fast computation by GAMESS programs complex [7]. A... 

For the nM+CrCl system the density functional theory (DFT) method with the B3LYP hybrid functional and the Huzinaga basis set were used, with the addition of two polarization r/-functions to the mini basis sets of all atoms except for potassium and also a single polarization/-function and a single diffuse p-function to the basis set of the chlorine atoms. In addition, for several structures, the act values were calculated using the MP2 method with the same basis set, as the principal calculations, but for the geometry that was obtained in advance using the unrestricted Hartree-Fock method with a somewhat lesser basis set (without addition of the polarization/-functions to the basis set of chlorine atoms). 

The smallest basis sets are called minimal basis sets. The most popular minimal basis set is the STO—3G set. This notation indicates that the basis set approximates the shape of a STO orbital by using a single contraction of three GTO orbitals. One such contraction would then be used for each orbital, which is the dehnition of a minimal basis. Minimal basis sets are used for very large molecules, qualitative results, and in certain cases quantitative results. There are STO—nG basis sets for n — 2—6. Another popular minimal basis set is the MINI set described below. 

MINI—i i = 1—4) These four sets have different numbers of primitives per contraction, mostly three or four. These are minimal basis sets with one contraction per orbital. Available for Li through Rn. 

For diatomic (and linear polyatomic) molecules, the basis set usually consists of several STOs centered on each atom. Thus the MOs are expressed as LCAOs—linear combinations of atomic orbitals. In a mini- ia/-basis-set calculation, only inner-shell and valence-shell STOs are used. Thus a minimal basis calculation of HF would use as basis functions l.sH, 1 F, 2jf, 2/ ctf, 2p7TF, 2pTTF, where 2poF is a fluorine 2p AO along the internuclear (z) axis (i.e., a 2pz AO), and the 2pir and 2pir AOs are... 

MINI A type of minimal basis set, the most common being MINI-1. 

Modihed JNeglect of Diatomic Overlap fMNDO) 3.10.4 Austin Model 1 (AMI) 86 87 5.4.3 MINI, MIDI and MAXI Basis Sets 5.4.4 Atomic Natural Orbitals Basis Sets 161 161... 

Table 18 Dipole moments (D)a for thiirane and thiirene calculated with the STO-3G, MINI-1, 3-21G/LWD and 6-31G basis sets.

The density functional theory (DFT) was employed for calculations using the B3LYP1 functional with the MINI/EPRII (C, N), TZV (Ni) basis sets. The standard PC GAMESS [11] software was used. 

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