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

NIST policy on privacy, security, and accessibility.

Please rate our products
© 2013 copyright by the U.S. Secretary of Commerce on behalf of the United States of America. All rights reserved.

The National Institute of Standards and Technology (NIST) is an agency of the U.S. Department of Commerce.

Please send questions, comments, corrections, additions and suggestions to

return to home page

II.A.1. (XV.A.)

Listing of experimental data for CH3SeH (Methane selenol)

State Conformation
1A' CS
Enthalpy of formation (Hfg), Entropy, Integrated heat capacity (0 K to 298.15 K) (HH), Heat Capacity (Cp)
Property Value Uncertainty units Reference Comment
Barrier to Internal Rotation 4.2   kJ mol-1 1973Tho:70
Information can also be found for this species in the NIST Chemistry Webbook
Vibrational levels (cm-1) vibrations
Mode Number Symmetry Frequency (cm-1) Frequency Reference Intensity (km mol-1) Int. unc. Intensity Reference Comment
1 A' 3027 1966Har/Wil:678      
2 A' 2955        
3 A' 2330        
4 A' 1447        
5 A' 1288        
6 A' 980        
7 A' 712        
8 A' 590        
9 A" 3032        
10 A" 1433        
11 A" 921        
12 A" 145        

vibrational zero-point energy: 9430.0 cm-1
Calculated vibrational frequencies for CH3SeH (Methane selenol).
Rotational Constants (cm-1) rotational constants
See section I.F.4 to change rotational constant units
A B C reference comment
3.12640 0.31156 0.29962 1973Tho:70

Calculated rotational constants for CH3SeH (Methane selenol).

Product of moments of inertia moments of inertia
16414.61amu3Å6   7.51620367190625E-116gm3 cm6
Geometric Data
picture of Methane selenol

Point Group Cs

Internal coordinates
distances (r) in Å, angles (a) in degrees, dihedrals (d) in degrees

Description Value unc. Connectivity Reference Comment
Atom 1 Atom 2 Atom 3 Atom 4
rHSe 1.473 0.020 1 3 1976Hellwege(II/7) r0
rCSe 1.959 0.010 1 2 1976Hellwege(II/7)
rCH 1.088 0.010 2 4 1976Hellwege(II/7)
aHSeC 95.45 2 2 1 3 1976Hellwege(II/7)
aHCH 110 1 4 2 5 1976Hellwege(II/7) methyl tilt = 1.5


Atom x (Å) y (Å) z (Å)
Se1 0.0327 -0.4217 0.0000
C2 0.0327 1.5373 0.0000
H3 -1.4336 -0.5616 0.0000
H4 1.0703 1.8645 0.0000
H5 -0.4722 1.9049 0.8909
H6 -0.4722 1.9049 -0.8909

Atom - Atom Distances bond lengths
Distances in Å

  Se1 C2 H3 H4 H5 H6
Se1   1.95901.47302.51062.54202.5420
C2 1.9590   2.56041.08801.08801.0880
H3 1.47302.5604   3.48652.79312.7931
H4 2.51061.08803.4865   1.78181.7818
H5 2.54201.08802.79311.7818   1.7818
H6 2.54201.08802.79311.78181.7818  

Calculated geometries for CH3SeH (Methane selenol).

Experimental Bond Angles (degrees) from cartesians bond angles

atom1 atom2 atom3 angle         atom1 atom2 atom3 angle
Se1 C2 H4 107.500 Se1 C2 H5 109.745
Se1 C2 H6 109.745 C2 Se1 H3 95.450
H4 C2 H5 109.938 H4 C2 H6 109.938
H5 C2 H6 109.938

Bond descriptions

Examples: C-C single bond, C=C, double bond, C#C triple bond, C:C aromatic bond
Bond Type Count
C-Se 1
H-Se 1
H-C 3


Atom 1 Atom 2
Se1 C2
Se1 H3
C2 H4
C2 H5
C2 H6
Electronic energy levels (cm-1)
Energy (cm-1) Degeneracy reference description
0 1   1A'
Dipole, Quadrupole and Polarizability
Electric dipole moment dipole
Dipole (Debye) Reference comment
1.291 1973Tho:70 x=a y=b

Calculated electric dipole moments for CH3SeH (Methane selenol).
Electric quadrupole moment quadrupole
Calculated electric quadrupole moments for CH3SeH (Methane selenol).

By selecting the following links, you may be leaving NIST webspace. We have provided these links to other web sites because they may have information that would be of interest to you. No inferences should be drawn on account of other sites being referenced, or not, from this page. There may be other web sites that are more appropriate for your purpose. NIST does not necessarily endorse the views expressed, or concur with the facts presented on these sites. Further, NIST does not endorse any commercial products that may be mentioned on these sites. Please address comments about this page to
squib reference DOI
1966Har/Wil:678 AB Harvey, MK Wilson "Vibrational Spectrum of Methaneselenol" J. Chem. Phys. 45, 678 (1966) 10.1063/1.1727628
1973Tho:70 CH Thomas "Microwave spectrum, barrier to internal rotation, structure, and dipole moment of methane selenol" J. Chem. Phys. 59(1), 70, 1973 10.1063/1.1679859
1976Hellwege(II/7) Hellwege, KH and AM Hellwege (ed.). Landolt-Bornstein: Group II: Atomic and Molecular Physics Volume 7: Structure Data of Free Polyatomic Molecules. Springer-Verlag. Berlin. 1976.  

Got a better number? Please email us at