Cartesian gaussian functions used in NWChem

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8:22:19 AM PDT - Thu, Jul 25th 2013
Hi, NWChem uses cartesian gaussian functions(cgf) as basis functions. For d-type cgf, there are 6 functions, among which only 5 are independent and the extra one are s-type symmetry function. For f-type cgf, there are 10 functions, among which only 7 are independent are the extra 3 are p-type symmetry functions. It seems that NWChem uses all 6 d-type functions and all 10 f-type functions, so this will introduce many linear dependence functions in the basis set. How does the NWChem handle this problem? thanks,

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9:55:26 AM PDT - Thu, Jul 25th 2013
spherical functions available
Alexx, You have the option of switching to a basis set that makes use of spherical functions by adding the keyword "spherical" to the basis set section label, as descrived in the documentation http://nwchemgit.github.io/index.php/Release62:Basis Using spherical functions, you have 6 d orbitals and 7 f orbitals. When linear dependence is present we do apply the Lowdin canonical orthogonalization method (as described - for example - in the Szabo & Ostlund book). Cheers, Edo