A systematic preparation of new contracted Gaussian‐type orbital sets. III. Second‐row atoms from Li through ne

Abstract

Four minimal Gaussian basis sets are generated for the second-row atoms Li through Ne. The first one, MINI-1, consists of a 3-term contraction of primitive Gaussian-type orbitals for Is, 2s, and 2p atomic orbitals. The convenient shorthand notation would be (3,3) for Li-Be and (3,3/3) for B-Ne. The second one, MINI-2, can be represented by (3,3/4) for B-Ne. In the same way, MINI-3 is described as (4,3) for Li-Be, and MINI-3 and MINI-4 are represented by (4,3/3) and (4,3/4) for B-Ne, respectively Although the four basis sets are the minimal type, they give the valence shell orbital energies which are close to those of DZ. These four and other sets derived from them are tested for the hetero-and homodiatomic molecules and some organic molecules. They are found to give the orbital energies that agree well with those given by extended calculations. Atomization energies and other spectroscopic constants are also calculated and compared with those of extended calculations. The results clearly indicate that the present basis sets can be used very effectively in the molecular calculations.

Basis-set dependence of theoretical deformation density in NO2 −

“…The MIDI4 basis set consists of three s-and two p-type contracted Gaussian functions for first-row atoms and two s-type functions for hydrogen. For the MIDI4* basis set, one group of d-type polarization function was added for first-row atoms and one group of p-type function for hydrogen (Tatewaki & Huzinaga, 1980). The basis-set dependence was also examined for related ions and molecules for comparison: NO; with the N-O bond length 1.25 A from the neutron study of LiNOa.3H20 (Hermansson, Thomas & Olovsson, 1980); HCOO-with the C-O and C-H bond lengths 1.25 and 1.09 A respectively and the O-C-O bond angle 125.5 ° from the neutron studies of LiHCOO.H20 (Tellgren, Ramanujam & Liminga, 1974) and NaHCOO (Fuess, Bats, Dann6hl, Meyer & Schweig, 1982); C2H6 in the staggered conformation with the C-C and C-H bond lengths 1.541 and 1-091 A respectively; and HNO2 assuming that the geometry of the NO 2 group is the same as that of NO2 with the N-H bond length 1.06 A.…”

Synthesis, hydrolysis, biochemical and theoretical evaluation of 1,4-bis(alkoxycarbonyl)azetidin-2-ones as potential elastase inhibitors

“…45,46 They were performed with Gaussian 94 47,48 on two computers, a Dec Alpha 8400 8-processor and a Dec Alpha 4100 4-processor running Digital Unix. The starting geometries were sketched drawn by standard fragments and then completely optimized following all the 3N-6 degrees of freedom either for the minima or the transition state structures.…”

Coherent control of electrons in molecules

“…All energies in the ground state and the first five low-lying excited states are calculated by configuration interaction (CI) methods. MINI4 basis sets (20) are used for all hydrogen and two carbon atoms in the methyl groups, and MINI4+double zeta basis sets (21) are used for all other atoms. There are 39 occupied MOs in DMABN with 78 electrons; 34 orbitals with lower orbital energies were considered as the internal orbitals and the remaining 5 occupied MOs with higher orbital energies and the lowest 5 virtual MOs were included in the CI computations with single and double excitations.…”

“…For simplicity without losing generality, eq. [20] can be rewritten as [21] I Y c o ) =~I + a e -'~l~I where @ is the phase difference between the two laser field and a is the coefficient related to the laser amplitude E through RAbi frequency R. Putting eqs. [18] and [19] into eq.…”