Basis functions Gaussian lobe

Li+ + H2 (H2 distance close to equilibrium) SCF + estimate of correlation energy (extended sp basis of Gaussian lobe functions) 2 60... 

POLARIZATION FUNCTIONS, GAUSSIAN LOBES AND HIGHER-ORDER GAUSSIAN BASIS SETS... 

Contracted gaussian lobes (i.e. combinations of only simple gaussians) are frequently used as basis functions (21). For large molecules the lobes may be... 

A minimal basis set of STO (expanded in Gaussian lobe functions) was used, and the least-energy pathway determined, assuming fixed values for some of the parameters. The complete optimization is not practicable for systems of this size and most surface studies make physically reasonable approximations to reduce the number of variables. The computed pathway is a non-least-motion rearrangement. The implications of the results with respect to the stability of F2NOF relative to F3NO were also discussed. 

A related set of calculations by Hart115 also studied NH30 and its stability with respect to NELOH. Gaussian lobe basis functions with a similar quality basis set to that in earlier work were used.116... 

The Gaussian lobe function method was introduced by Preuss and developed for routine calculations by Whitten. The contraction of Gaussian lobe function (GLF) basis sets is made along the same lines as with Cartesian GTF s. As regards the primitives, the s-type functions are expressed in the usual way. But the primitives of p, d, f,. .. types are expressed as linear combinations of s-Gaussians (lobe functions) placed at different points so as to retain the proper symmetry (see Fig. 2,4 ). Thus, a p-type function on nucleus A may be... 

Our first computer implementation of Eq. 31 was used to evaluate the difference between the energy of the total system and that of the environment (Es pa, Pu Ehk[pb ) at the LDA level50, ft was developed as an interface for hybrid quantum mechanics/classical molecular dynamics simulations52,50,51. The atomic basis sets used in this implementations were restricted to have the form of gaussian lobe functions introduced by Whitten115. 

In other cases, as for example in the study of cis-trans isomerization of glyoxal i68), the basis was constructed upon gaussian lobe functions, as prescribed by Whitten 16 ). 

A few ab initio SCF-MO calculations showed that i is very sensitive to changes in basis set. Minimal basis sets of Slater and of Gaussian lobe functions gave i = +0.656 [2, 3] and +0.506... 

The rnethod used constructs the one-electron Bloch orbitals as a linear combination of a double-C (split-shell) type atomic basis set, i.e., 10 and 18 contracted atomic orbitals are applied on atoms N and S, respectively. These atomic orbitals themselves are taken as contractions of Gaussian lobe functions using 25 and 46 primitive functions for atoms N and S, respectively. The exponents of the Gaussians as well as the contraction coefficients were taken from the paper of Roos et Based... 

Scaling the Gaussians from the variational fit to the H atom is easy in the lobe basis. Once the exponent is modified, the function is renormalized by dividing the coefficients by the square root of the overlap of the total orbital with itself. 

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