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All results from a given calculation for CH2 (Methylene)

using model chemistry: MP2/cc-pVQZ

19 10 17 12 22

States and conformations

State Conformation minimum conformation conformer description state description
1 1 yes C2V 3B1
1 2 no D*H 3Σg
2 1 yes C2V 1A1

State 1 (3B1) , Conformer 1 (C2V)

Jump to S1C2 S2C1 S2C2
Energy calculated at MP2/cc-pVQZ
 hartrees
Energy at 0K-39.066019
Energy at 298.15K-39.065835
HF Energy-38.940318
Nuclear repulsion energy6.191489
The energy at 298.15K was derived from the energy at 0K and an integrated heat capacity that used the calculated vibrational frequencies.
Vibrational Frequencies calculated at MP2/cc-pVQZ
Mode Number Symmetry Frequency
(cm-1)
Scaled Frequency
(cm-1)
IR Intensities
(km mol-1)
Raman Act
4/u)
Dep P Dep U
1 A1 3208 3043 0.76      
2 A1 1138 1079 7.63      
3 B2 3444 3266 0.91      

Unscaled Zero Point Vibrational Energy (zpe) 3894.9 cm-1
Scaled (by 0.9484) Zero Point Vibrational Energy (zpe) 3693.9 cm-1
See section III.C.1 List or set vibrational scaling factors to change the scale factors used here.
See section III.C.2 Calculate a vibrational scaling factor for a given set of molecules to determine the least squares best scaling factor.
Rotational Constants (cm-1) from geometry optimized at MP2/cc-pVQZ
ABC
53.30494 8.65388 7.44518

See section I.F.4 to change rotational constant units
Geometric Data calculated at MP2/cc-pVQZ

Point Group is C2v

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
C1 0.000 0.000 0.107
H2 0.000 0.983 -0.321
H3 0.000 -0.983 -0.321

Atom - Atom Distances (Å)
  C1 H2 H3
C11.07221.0722
H21.07221.9661
H31.07221.9661

picture of Methylene state 1 conformation 1
More geometry information
Calculated Bond Angles
atom1 atom2 atom3 angle atom1 atom2 atom3 angle
H2 C1 H3 132.939
Electronic energy levels
Charges, Dipole, Quadrupole and Polarizability

State 1 (3Σg) , Conformer 2 (D*H)

Jump to S1C1 S2C1 S2C2
Energy calculated at MP2/cc-pVQZ
 hartrees
Energy at 0K-39.055728
Energy at 298.15K 
HF Energy-38.928349
Nuclear repulsion energy6.236643
The energy at 298.15K was derived from the energy at 0K and an integrated heat capacity that used the calculated vibrational frequencies.
Vibrational Frequencies calculated at MP2/cc-pVQZ
Mode Number Symmetry Frequency
(cm-1)
Scaled Frequency
(cm-1)
IR Intensities
(km mol-1)
Raman Act
4/u)
Dep P Dep U
1 Σg 3285 3115 0.00      
2 Σu 3635 3447 73.94      
3 Πu 1068i 1013i 108.46      
4 Πu 1068i 1013i 108.46      

Unscaled Zero Point Vibrational Energy (zpe) 2391.5 cm-1
Scaled (by 0.9484) Zero Point Vibrational Energy (zpe) 2268.1 cm-1
See section III.C.1 List or set vibrational scaling factors to change the scale factors used here.
See section III.C.2 Calculate a vibrational scaling factor for a given set of molecules to determine the least squares best scaling factor.
Rotational Constants (cm-1) from geometry optimized at MP2/cc-pVQZ
B
7.43466

See section I.F.4 to change rotational constant units
Geometric Data calculated at MP2/cc-pVQZ

Point Group is D∞h

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
C1 0.000 0.000 0.000
H2 0.000 0.000 1.061
H3 0.000 0.000 -1.061

Atom - Atom Distances (Å)
  C1 H2 H3
C11.06061.0606
H21.06062.1212
H31.06062.1212

picture of Methylene state 1 conformation 2
More geometry information
Calculated Bond Angles
atom1 atom2 atom3 angle atom1 atom2 atom3 angle
H2 C1 H3 180.000
Electronic energy levels
Charges, Dipole, Quadrupole and Polarizability

State 2 (1A1) , Conformer 1 (C2V)

Jump to S1C1 S1C2 S2C2
Energy calculated at MP2/cc-pVQZ
 hartrees
Energy at 0K-39.043304
Energy at 298.15K-39.043141
HF Energy-38.895235
Nuclear repulsion energy6.068494
The energy at 298.15K was derived from the energy at 0K and an integrated heat capacity that used the calculated vibrational frequencies.
Vibrational Frequencies calculated at MP2/cc-pVQZ
Mode Number Symmetry Frequency
(cm-1)
Scaled Frequency
(cm-1)
IR Intensities
(km mol-1)
Raman Act
4/u)
Dep P Dep U
1 A1 3000 2845 60.60      
2 A1 1425 1352 1.99      
3 B2 3079 2920 59.77      

Unscaled Zero Point Vibrational Energy (zpe) 3751.9 cm-1
Scaled (by 0.9484) Zero Point Vibrational Energy (zpe) 3558.3 cm-1
See section III.C.1 List or set vibrational scaling factors to change the scale factors used here.
See section III.C.2 Calculate a vibrational scaling factor for a given set of molecules to determine the least squares best scaling factor.
Rotational Constants (cm-1) from geometry optimized at MP2/cc-pVQZ
ABC
20.32422 11.38103 7.29566

See section I.F.4 to change rotational constant units
Geometric Data calculated at MP2/cc-pVQZ

Point Group is C2v

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
C1 0.000 0.000 0.173
H2 0.000 0.857 -0.520
H3 0.000 -0.857 -0.520

Atom - Atom Distances (Å)
  C1 H2 H3
C11.10251.1025
H21.10251.7145
H31.10251.7145

picture of Methylene state 2 conformation 1
More geometry information
Electronic energy levels
Charges, Dipole, Quadrupole and Polarizability

State 2 () , Conformer 2 ()

Jump to S1C1 S1C2 S2C1
Energy calculated at MP2/cc-pVQZ
 hartrees
Energy at 0K-39.043304
Energy at 298.15K-39.043141
HF Energy-38.895235
Nuclear repulsion energy6.068494
The energy at 298.15K was derived from the energy at 0K and an integrated heat capacity that used the calculated vibrational frequencies.
Vibrational Frequencies calculated at MP2/cc-pVQZ
Rotational Constants (cm-1) from geometry optimized at MP2/cc-pVQZ
ABC
20.32422 11.38103 7.29566

See section I.F.4 to change rotational constant units
Geometric Data calculated at MP2/cc-pVQZ

Point Group is C2v

Electronic energy levels
Charges, Dipole, Quadrupole and Polarizability