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
VIII	Links to other sites
IX	Feedback
X	Older CCCBDB versions
XII	Geometries
XIII	Vibrations
XIV	Reaction data
XV	Entropy data
XVI	Bibliographic data
XVII	Ion data
XVIII	Bad calculations
XIX	Index of properties
XX	H-bond dimers
XXI	Oddities

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IV.D.4. (XII.A.2.)

Compare Bonds

18 10 19 16 31

B2PLYP=FULL/6-311+G(3df,2p) for rSiSi

Histogram of Bond length differences (in Å) vs number of species

Differences greater than 0.350 are in the 0.350 bin. Differences less than -0.250 are in the -0.250 bin.

	10
	8
	6
	4
	2
	0
		-0.250			-0.200			-0.150			-0.100			-0.050			0.000			0.050			0.100			0.150			0.200			0.250			0.300			0.350
bond length difference calc. - exp. (Å)

	Species	Name	Difference (Å)
Most negative difference	Si2H2	disilyne	-0.242
Most positive difference	Si2H6	disilane	0.022

Bond lengths
Click on entry for experimental details.

Species	Name	Experimental (Å)	Difference (Å)
Si2H2	disilyne	2.215	-0.242
Si2H2	disilyne	2.215	-0.115
Si2H2	disilyne	2.215	-0.101
Si2H2	disilyne	2.215	-0.005
Si2H6	disilane	2.320	0.022