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baoilleach / qmspeedtest

Quantum Chemistry speed test
BSD 2-Clause "Simplified" License
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Use reasonable basis sets #9

Closed susilehtola closed 10 years ago

susilehtola commented 10 years ago

Using just the 6-31G basis set will give a huge advantage to obsolete programs. This is because the basis set doesn't have polarization functions, and it has S=P shells.

No polarization functions leads to the wrong geometries.

You should use at least something like cc-pVDZ to get sane geometries at HF level, and cc-pVTZ at DFT level.

baoilleach commented 10 years ago

The small basis set size was simply chosen to make it easier for me to begin this speed test. Later tests may use larger basis sets.