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faq:cutoff [2014/02/20 13:59]
krack
faq:cutoff [2014/02/20 14:00] (current)
krack Bold
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 ===== How can one guess a reasonable cutoff value? ===== ===== How can one guess a reasonable cutoff value? =====
-**This is for the impatient CP2K user:** As a rule of thumb one can multiply the largest exponent of the Gaussian basis sets employed by 40 to obtain a reasonable guess for the cutoff value in Rydberg. The first column of the CP2K basis set format contains the Gaussian exponents, e.g. for the oxygen DZVP-MOLOPT-SR-GTH basis set you may find a value of about 10.4 and the corresponding hydrogen DZVP-MOLOPT-SR-GTH basis set employs a largest exponent of about 10.0. Thus a cutoff value of 10*40 = 400 Rydberg would be a reasonable guess for a cutoff value to start with. The following values+**This is for the impatient CP2K user:** As a rule of thumb one can multiply the largest exponent of the Gaussian basis sets employed by **40** to obtain a reasonable guess for the cutoff value in Rydberg. The first column of the CP2K basis set format contains the Gaussian exponents, e.g. for the oxygen DZVP-MOLOPT-SR-GTH basis set you may find a value of about 10.4 and the corresponding hydrogen DZVP-MOLOPT-SR-GTH basis set employs a largest exponent of about 10.0. Thus a cutoff value of **10*40 = 400 Rydberg** would be a reasonable guess for a cutoff value to start with. The following values
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 Total charge density on r-space grids: ​       0.0000000000 Total charge density on r-space grids: ​       0.0000000000
faq/cutoff.txt ยท Last modified: 2014/02/20 14:00 by krack