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

Listing of experimental data for CH3PH2 (Methyl phosphine)

Other names
Methylphosphine; Phosphine, methyl-;
InChI=1/CH5P/c1-2/h2H2,1H3 PC Methylphosphine
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
Hfg(298.15K) enthalpy of formation     kJ mol-1 webbook
Hfg(0K) enthalpy of formation     kJ mol-1 webbook
Entropy (298.15K) entropy     J K-1 mol-1  
Integrated Heat Capacity (0 to 298.15K) integrated heat capacity     kJ mol-1  
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' 3000 1974sve/kov      
2 A' 2938 1974sve/kov      
3 A' 2297 1974sve/kov      
4 A' 1450 1974sve/kov      
5 A' 1238 1974sve/kov      
6 A' 1086 1974sve/kov      
7 A' 977 1974sve/kov      
8 A' 740 1974sve/kov      
9 A' 677 1974sve/kov      
10 A" 2992 1974sve/kov      
11 A" 2312 1974sve/kov      
12 A" 1450 1974sve/kov      
13 A" 1017 1974sve/kov      
15 A" 207 1974sve/kov      

Calculated vibrational frequencies for CH3PH2 (Methyl phosphine).
Rotational Constants (cm-1) rotational constants
See section I.F.4 to change rotational constant units
A B C reference comment

Calculated rotational constants for CH3PH2 (Methyl phosphine).

Product of moments of inertia moments of inertia
amu3Å6   0gm3 cm6

Geometric Data
picture of Methyl phosphine

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
rCP 1.858   1 2 1976Hellwege(II/7)
rCH 1.094   1 3 1976Hellwege(II/7)
rPH 1.423   2 6 1976Hellwege(II/7)
aHCP 109.6 2 1 3 1976Hellwege(II/7)
aHPC 96.5 1 2 6 1976Hellwege(II/7) !assumed

These cartesians were determined using some assumed coordinate values. Cartesians
Atom x (Å) y (Å) z (Å)

Atom - Atom Distances bond lengths
Distances in Å

Calculated geometries for CH3PH2 (Methyl phosphine).

Bond descriptions
Examples: C-C single bond, C=C, double bond, C#C triple bond, C:C aromatic bond
Bond Type Count
H-C 3
H-P 2
C-P 1

Atom 1 Atom 2
C1 P2
C1 H3
C1 H4
C1 H5
P2 H6
P2 H7

Electronic energy levels (cm-1)
Energy (cm-1) Degeneracy reference description
0 1   1A'

Ionization Energies (eV)
Ionization Energy I.E. unc. vertical I.E. v.I.E. unc. reference
9.120   9.620   webbook

Dipole, Quadrupole and Polarizability
Electric dipole moment dipole
Dipole (Debye) Reference comment
1.100 NSRDS-NBS10  

Calculated electric dipole moments for CH3PH2 (Methyl phosphine).
Electric quadrupole moment quadrupole
Calculated electric quadrupole moments for CH3PH2 (Methyl phosphine).

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squib reference DOI
1974sve/kov L.M. Sverdlov, M. A. Kovner, E. P. Krainov, "Vibrational Spectra of Polyatomic Molecules" Wiley, New York 1974  
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.  
NSRDS-NBS10 R. D. Nelson Jr., D. R. Lide, A. A. Maryott "Selected Values of electric dipole moments for molecules in the gas phase" NSRDS-NBS10, 1967  
webbook NIST Chemistry Webbook (  

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