Quantum Chemistry Speed Test

The rules: Calculations must only use a single CPU. The B3LYP used should be that used by default by Gaussian and NWChem (namely the VWN3 not VWN5). And please, no Gaussian input files or results.

Various people have submitted results:

• Eric Berquist
• Michael Banck
• [Karol Langner] (http://github.com/langner/qmspeedtest)
• Noel O'Boyle
• Pedro Silva

Please fork the original repo and submit your own!

Pedro Silva's results

Machine: Intel(R) Core2 Quad Q8300@2.5 GHz with 3.9 GB memory with Ubuntu 10.04

Fancy compiler or maths libraries used when compiling: Gamess US was built using ATLAS math library. Q-Chem inputs were takien from Michael Banck

HF

QM Package	Time (min)	Steps	per step	Total E	HOMO	LUMO
Gamess(US)	9.2	30	0.31	-644.6757056212
Firefly	11.5	23	0.5	-644.6757047981
Q-Chem 4.0	4.96	14	0.35	-644.675706161

B3LYP

Default grids are different in each program:

• Gamess (US) uses a Lebedev grid with 96 radial points per atom and 302 angular points per radial shell
• Firefly uses a pruned Lebedev grid with 63 radial points per atom and 302 angular points per radial shell
• Q-Chem uses the "standard grid-1" , which is a pruned version of a Lebedev grid with 50 radial points per atom and 194 angular points per radial shell.

QM Package	Time (min)	Steps	per step	Total E	HOMO	LUMO
Gamess (US) default grid	142.2	41	3.47	-648.4956883277
Gamess (US) with Firefly grid	102.7	41	2.5	-648.4956642
Gamess (US) with SG-1 grid	24.7	40	0.62	-648.4956642

QM Package	Time (min)	Steps	per step	Total E	HOMO	LUMO
Firefly with Gamess(US) grid	33.7	26	1.3	-648.4956790
Firefly default grid	22.2	25	0.89	-648.4956786524
Firefly with SG-1 grid	19.6	23	0.85	-648.4957054791

QM Package	Time (min)	Steps	per step	Total E	HOMO	LUMO
Q-Chem 4.0 with Gamess (US) grid	32.5	14	2.32	-648.495693316716
Q-Chem 4.0 with Firefly grid	23.25	14	1.66	-648.495693748
Q-Chem 4.0 default grid	9.30	14	0.66	-648.495723731