Uniform quality constrained gaussian basis sets

1977 ◽  
Vol 55 (7) ◽  
pp. 1181-1192 ◽  
Author(s):  
Paul G. Mezey ◽  
Imre G. Csizmadia
Keyword(s):  
Ab Initio ◽  
Optimization Technique ◽  
Quality Criterion ◽  
Basis Sets ◽  
Integration Time ◽  
Program System ◽  
Gaussian Basis Sets ◽  
Direct Optimization ◽  
Time Saving ◽  
Exponent Sets

Uniformly balanced (6S3P), (7S3P), and (8S4P) gaussian basis sets with identical exponent sets for functions describing the 2s and 2p subshells have been obtained for the first row atoms. The basis sets have been determined using a direct optimization technique; they are thoroughly balanced and satisfy a rigorous quality criterion. These uniform quality constrained basis sets were designed for applications in ab initio programs of the type of the GAUSSIAN 70 program system, that may utilize the integration-time saving constraint α2s = α2p.

Evaluation of Gaussian basis sets in ab initio

1983 ◽  
Vol 111 ◽  
pp. 387-396 ◽  
Author(s):  
John W. Jost ◽  
Chester T. O'Konski
Keyword(s):  
Ab Initio ◽  
Basis Sets ◽  
Gaussian Basis Sets

Gaussian basis sets for ab initio calculation of NLO properties of polyatomic molecules

2010 ◽  
Vol 10 (3-6) ◽  
pp. 239-256
Author(s):  
Diego Paschoal ◽  
Marcello F. Costa ◽  
Georgia M.A. Junqueira ◽  
Hélio F. Dos Santos
Keyword(s):  
Ab Initio ◽  
Ab Initio Calculation ◽  
Polyatomic Molecules ◽  
Basis Sets ◽  
Gaussian Basis Sets ◽  
Nlo Properties

Experimental Gas Phase 1H NMR Spectra and Basis Set Dependence of ab initio GIAOMO Calculations of 1H and 13C NMR Absolute Shieldings and Chemical Shifts of Small Hydrocarbons

2004 ◽  
Vol 59 (10) ◽  
pp. 1153-1176 ◽  
Author(s):  
Thomas Zuschneid ◽  
Holger Fischer ◽  
Thomas Handel ◽  
Klaus Albert ◽  
Günter Häfelinger
Keyword(s):  
Ab Initio ◽  
Gas Phase ◽  
Nmr Spectra ◽  
Chemical Shifts ◽  
Basis Set ◽  
Basis Sets ◽  
Gaussian Basis Sets ◽  
Phase Measurements ◽  
H Nmr ◽  
Set Up

AbstractHigh-resolution gas phase measurements of 1H NMR spectra at 400 MHz and atmospheric pressure of seven small hydrocarbons are presented. The developed new method and the experimental set-up are described. Ab initio GIAO MO calculations of 1H and 13C NMR absolute shieldings on the HF, MP2 and B3LYP levels using 25 standard gaussian basis sets are reported for these hydrocarbons, based on experimental re distances. The measured gas phase 1H chemical shifts have been converted to an absolute σ0 shielding scale by use of the literature shielding of methane. These and gas phase 13C literature values have been transferred with literature ZPV data to estimated σeexp shieldings which are used to evaluate the basis set dependence of the calculated σe shieldings utilizing linear least squares regressions. Exponential extrapolations of Dunning basis set calculations allow the determination of basis set limits for 1H and 13C shieldings. 1H and 13C chemical shifts have been derived from the HF calculated shieldings with shieldings of TMS which has been geometry optimized and GIAO calculated in each basis. Standard deviations (esd) as low as 0.09 ppm for 1H and 0.76 ppm for 13C calculations have been obtained.The statistically best basis set for simultaneous calculation of 1H and 13C absolute shieldings or relative shifts is 6-311G* within the HF and B3LYP methods. Aiming for highest accuracy and precision, 1H and 13C have to be treated separately. In this case, best results are obtained using MP2/6-311G** or higher for 1H shieldings and MP2/cc-pVTZ for 13C shieldings.

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