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

Listing of experimental data for CH2PH (H2CPH)

Other names
Phosphethene; methylenephosphine;
InChI=1/CH3P/c1-2/h2H,1H2 [CH2]=[PH] methylenephosphine
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 -281.83   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

Calculated vibrational frequencies for CH2PH (H2CPH).
Rotational Constants (cm-1) rotational constants
See section I.F.4 to change rotational constant units
A B C reference comment
4.61997 0.54765 0.48864 1981Kro/Nix:367

Calculated rotational constants for CH2PH (H2CPH).

Product of moments of inertia moments of inertia
3874.881amu3Å6   1.77429731942402E-116gm3 cm6

Geometric Data
picture of H2CPH

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
rCH 1.090 0.015 1 3 1981Kro/Nix:367 cis
rCH 1.090 0.015 1 4 1981Kro/Nix:367 trans
rCP 1.673 0.002 1 2 1981Kro/Nix:367
rPH 1.420 0.006 2 5 1981Kro/Nix:367
aHCP 124.4 0.8 2 1 3 1981Kro/Nix:367 cis H
aHCP 118.4 1.2 2 1 4 1981Kro/Nix:367 trans H
aHCH 117.2 1.2 3 1 4 1981Kro/Nix:367
aHPC 97.4 0.4 1 2 5 1981Kro/Nix:367
dHCPH 0 3 1 2 5 1981Kro/Nix:367

Atom x (Å) y (Å) z (Å)

Atom - Atom Distances bond lengths
Distances in Å

Calculated geometries for CH2PH (H2CPH).

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

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

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
    10.300 0.200 1981Kro/Nix:367

Dipole, Quadrupole and Polarizability
Electric dipole moment dipole
Dipole (Debye) Reference comment
0.869 1981Kro/Nix:367 mua=0.731, mub=0.470

Calculated electric dipole moments for CH2PH (H2CPH).
Electric quadrupole moment quadrupole
Calculated electric quadrupole moments for CH2PH (H2CPH).

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