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All results from a given calculation for CH2 (Methylene)

using model chemistry: MP2=FULL/3-21G*

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=FULL/3-21G*
 hartrees
Energy at 0K-38.763281
Energy at 298.15K-38.763103
HF Energy-38.708957
Nuclear repulsion energy6.151364
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=FULL/3-21G*
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 3189 3023 0.52      
2 A1 1199 1137 3.05      
3 B2 3405 3227 3.57      

Unscaled Zero Point Vibrational Energy (zpe) 3896.5 cm-1
Scaled (by 0.948) Zero Point Vibrational Energy (zpe) 3693.8 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=FULL/3-21G*
ABC
48.27051 8.68260 7.35892

See section I.F.4 to change rotational constant units
Geometric Data calculated at MP2=FULL/3-21G*

Point Group is C2v

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
C1 0.000 0.000 0.112
H2 0.000 0.981 -0.337
H3 0.000 -0.981 -0.337

Atom - Atom Distances (Å)
  C1 H2 H3
C11.07961.0796
H21.07961.9629
H31.07961.9629

picture of Methylene state 1 conformation 1
More geometry information
Calculated Bond Angles
atom1 atom2 atom3 angle atom1 atom2 atom3 angle
H2 C1 H3 130.751
Electronic energy levels
Charges, Dipole, Quadrupole and Polarizability

State 1 (3Σg) , Conformer 2 (D*H)

Jump to S1C1 S2C1 S2C2
Energy calculated at MP2=FULL/3-21G*
 hartrees
Energy at 0K-38.750187
Energy at 298.15K 
HF Energy-38.697438
Nuclear repulsion energy6.187019
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=FULL/3-21G*
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 3236 3068 0.00      
2 Σu 3576 3390 29.36      
3 Πu 1152i 1092i 127.27      
3 Πu 1152i 1092i 127.27      

Unscaled Zero Point Vibrational Energy (zpe) 2254.2 cm-1
Scaled (by 0.948) Zero Point Vibrational Energy (zpe) 2137.0 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=FULL/3-21G*
B
7.31681

See section I.F.4 to change rotational constant units
Geometric Data calculated at MP2=FULL/3-21G*

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 1.069
H3 0.000 0.000 -1.069

Atom - Atom Distances (Å)
  C1 H2 H3
C11.06911.0691
H21.06912.1383
H31.06912.1383

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=FULL/3-21G*
 hartrees
Energy at 0K-38.718589
Energy at 298.15K-38.718428
HF Energy-38.651552
Nuclear repulsion energy5.980221
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=FULL/3-21G*
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 2878 2729 70.90      
2 A1 1494 1416 5.13      
3 B2 2945 2792 125.28      

Unscaled Zero Point Vibrational Energy (zpe) 3658.4 cm-1
Scaled (by 0.948) Zero Point Vibrational Energy (zpe) 3468.2 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=FULL/3-21G*
ABC
20.32897 10.86218 7.07948

See section I.F.4 to change rotational constant units
Geometric Data calculated at MP2=FULL/3-21G*

Point Group is C2v

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
C1 0.000 0.000 0.173
H2 0.000 0.877 -0.520
H3 0.000 -0.877 -0.520

Atom - Atom Distances (Å)
  C1 H2 H3
C11.11821.1182
H21.11821.7549
H31.11821.7549

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=FULL/3-21G*
 hartrees
Energy at 0K-38.718589
Energy at 298.15K-38.718428
HF Energy-38.651552
Nuclear repulsion energy5.980221
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=FULL/3-21G*
Rotational Constants (cm-1) from geometry optimized at MP2=FULL/3-21G*
ABC
20.32897 10.86218 7.07948

See section I.F.4 to change rotational constant units
Geometric Data calculated at MP2=FULL/3-21G*

Point Group is C2v

Electronic energy levels
Charges, Dipole, Quadrupole and Polarizability