【摘 要】
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Global orbital cutoff values and numerical basis sets are generally employed to facilitate the self-consistence field convergence in theoretical computations.The selection of right global orbital cuto
【机 构】
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Key Laboratory for Macromolecular Science of Shaanxi Province,School of Chemistry & Chemical Enginee
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Global orbital cutoff values and numerical basis sets are generally employed to facilitate the self-consistence field convergence in theoretical computations.The selection of right global orbital cutoff values and numerical basis sets is important to the computational accuracies and efficiencies.In this study,the effects of global orbital cutoff and numerical basis sets on the theoretical atomization energies(D0)using the density functional theory with generalized gradient approximation were investigated.The effects of global orbital cutoff values on D0,the calculations on a set of 44 small molecules were performed with two different functionals: BLYP and HTCH with electron smearing values of 0.005 Ha and zero(Fermi occupation).DNP basis set was used in the present study.The global orbital cutoff values were increased from 3.0 to 10.0(A)(Fig.1).Our results on the D0 of a set of 44 molecules demonstrate the numerical orbital cutoff value should be larger than 6.5(A)to get the converged energetic properties.
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