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
X	Older CCCBDB versions
XII	Geometries
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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/6-31G(2df,p)

For ()

	Energy (hartrees)
frozen core	-4156.0746900
correlated core	-4156.1351091
difference	-0.0604191

	Energy (hartrees)
frozen core	-4156.0746408
correlated core	-4156.1351091
difference	-0.0604682

	Energy (hartrees)
frozen core	-4156.0746900
correlated core	-4156.1350615
difference	-0.0603716

	Energy (hartrees)
frozen core	-4156.0746408
correlated core	-4156.1350615
difference	-0.0604207