Sir:
Get your GAMESS manual and turn to Section 4-Further Information. A few
pages in you will find "Basis Set References," which discusses first
the STO-NG
class. There, in note 3, you will find that the scale factors used in GAMESS
for Na-Cl differ from those proposed by Pople. I suspect that Pople's code
uses his values; this may explain the difference you are seeing.
Happy crunching,
Mark
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