National Institute of Standards and Technology
Computational Chemistry Comparison and Benchmark DataBase
Release 17bSeptember 2015
NIST Standard Reference Database 101
IIExperimental data
IIICalculated data
IVData comparisons
VCost comparisons
VIInput and output files
VIITutorials and Units
VIIILinks to other sites
XOlder CCCBDB versions
XIII Vibrations
XIVReaction data
XVEntropy data
XVIBibliographic data
XVIIIon data
XVIIIBad calculations
XIXIndex of properties
XXH-bond dimers

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II.A.3. (XII.A.1.)

Listing of experimental geometry data for SiH2 (silicon dihydride)

Rotational Constants (cm-1)

See section I.F.4 to change rotational constant units
8.09898 7.02363 3.70257
Rotational Constants from 1999Hir/Ish:4254
Calculated rotational constants for SiH2 (silicon dihydride).

Point Group C2v

Internal coordinates

(distances (r) in Å) (angles (a) in degrees) (dihedrals (d) in degrees)
Description Value Connectivity Reference Comment
Atom 1 Atom 2 Atom 3 Atom 4
aHSiH 92 2 1 3 1998Gup/Pra:1607
rSiH 1.514 1 2 1998Gup/Pra:1607
picture of silicon dihydride

Bond descriptions

Examples: C-C single bond, C=C, double bond, C#C triple bond, C:C aromatic bond
Bond Type Count
H-Si 2

Atom x (Å) y (Å) z (Å)
Si1 0.0000 0.0000 0.0000
H2 0.0000 0.0000 -1.5141
H3 0.0000 1.5132 0.0528

Atom - Atom Distances (Å)

  Si1 H2 H3

Calculated geometries for SiH2 (silicon dihydride).
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squib reference DOI
1998Gup/Pra:1607 Gupte, Prasad, Ground State Geometries and Vibrational Spectra of Small Hyrdogenated Silicon Clusters Using Nonorthogonal Tight-binding Molecular Dynamics, Inter. J. of Mod. Phys. B, Vol. 12, #15, pgs. 1607-1622 10.1142/S0217979298000880
1999Hir/Ish:4254 Hirota, E.; Ishikawa, H. "The vibrational spectrum and molecular constants of silicon dihydride SiH2 in the ground electronic state." Journal of Chemical Physics. 110, 4254-4257 (1999) 10.1063/1.478308

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