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

Listing of experimental data for CH3SeH (Methane selenol)

InChI=1/CH4Se/c1-2/h2H,1H3 C[Se]
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

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
CSe 1
HSe 1
HC 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).

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squib reference DOI
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.  

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