National Institute of Standards and Technology

Computational Chemistry Comparison and Benchmark DataBase
Release 22	May 2022
NIST Standard Reference Database 101

I	Introduction
II	Experimental data
III	Calculated data
IV	Data comparisons
V	Cost comparisons
VI	Input and output files
VII	Tutorials and Units
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IX	Feedback
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XVI	Bibliographic data
XVII	Ion data
XVIII	Bad calculations
XIX	Index of properties
XX	H-bond dimers
XXI	Oddities

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III.G.10.a.

Energy differences between frozen core and full core for B2PLYP/3-21G*

For ()

	Energy (hartrees)
frozen core	-2068.1717039
correlated core	-2068.1748607
difference	-0.0031568

	Energy (hartrees)
frozen core	-2068.1716992
correlated core	-2068.1748607
difference	-0.0031615

	Energy (hartrees)
frozen core	-2068.1717039
correlated core	-2068.1748560
difference	-0.0031521

	Energy (hartrees)
frozen core	-2068.1716992
correlated core	-2068.1748560
difference	-0.0031568