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All results from a given calculation for C4H8 (methylcyclopropane)

using model chemistry: MP2/CEP-121G

19 10 17 12 22

States and conformations

State Conformation minimum conformation conformer description state description
1 1 yes CS 1A'
Energy calculated at MP2/CEP-121G
 hartrees
Energy at 0K-26.866961
Energy at 298.15K-26.875567
HF Energy-26.506125
Nuclear repulsion energy68.787565
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/CEP-121G
Mode Number Symmetry Frequency
(cm-1)
Scaled Frequency
(cm-1)
IR Intensities
(km mol-1)
Raman Act
4/u)
Dep P Dep U
1 A' 3206 3129 46.83      
2 A' 3114 3040 23.49      
3 A' 3092 3018 18.67      
4 A' 3054 2980 30.98      
5 A' 2953 2882 44.80      
6 A' 1534 1497 6.70      
7 A' 1520 1484 3.17      
8 A' 1452 1417 4.76      
9 A' 1410 1376 2.17      
10 A' 1238 1208 0.02      
11 A' 1223 1194 0.05      
12 A' 1127 1100 16.93      
13 A' 990 966 4.29      
14 A' 948 925 5.17      
15 A' 811 791 1.01      
16 A' 754 736 10.21      
17 A' 363 354 0.19      
18 A" 3189 3112 0.33      
19 A" 3081 3007 29.89      
20 A" 3057 2983 45.46      
21 A" 1522 1486 2.44      
22 A" 1495 1459 2.16      
23 A" 1224 1194 0.90      
24 A" 1191 1162 0.11      
25 A" 1138 1111 6.43      
26 A" 1123 1096 0.28      
27 A" 866 845 0.81      
28 A" 840 820 20.13      
29 A" 345 336 0.85      
30 A" 202 197 0.00      

Unscaled Zero Point Vibrational Energy (zpe) 24029.2 cm-1
Scaled (by 0.976) Zero Point Vibrational Energy (zpe) 23452.5 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/CEP-121G
ABC
0.49703 0.20268 0.17748

See section I.F.4 to change rotational constant units
Geometric Data calculated at MP2/CEP-121G

Point Group is Cs

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
C1 0.355 0.420 0.000
C2 -0.904 1.309 0.000
H3 1.305 0.966 0.000
C4 0.355 -0.921 0.780
C5 0.355 -0.921 -0.780
H6 1.272 -1.228 1.287
H7 1.272 -1.228 -1.287
H8 -0.571 -1.210 1.284
H9 -0.571 -1.210 -1.284
H10 -1.814 0.682 0.000
H11 -0.931 1.955 0.896
H12 -0.931 1.955 -0.896

Atom - Atom Distances (Å)
  C1 C2 H3 C4 C5 H6 H7 H8 H9 H10 H11 H12
C11.54171.09491.55121.55122.28302.28302.27202.27202.18562.19382.1938
C21.54172.23542.67732.67733.58173.58172.84682.84681.10511.10441.1044
H31.09492.23542.25142.25142.54342.54343.14613.14613.13192.60372.6037
C41.55122.67732.25141.55901.09182.28171.09322.27992.80843.15263.5681
C51.55122.67732.25141.55902.28171.09182.27991.09322.80843.56813.1526
H62.28303.58172.54341.09182.28172.57461.84283.16323.85123.89034.4437
H72.28303.58172.54342.28171.09182.57463.16321.84283.85124.44373.8903
H82.27202.84683.14611.09322.27991.84283.16322.56742.60303.20863.8593
H92.27202.84683.14612.27991.09323.16321.84282.56742.60303.85933.2086
H102.18561.10513.13192.80842.80843.85123.85122.60302.60301.78921.7892
H112.19381.10442.60373.15263.56813.89034.44373.20863.85931.78921.7913
H122.19381.10442.60373.56813.15264.44373.89033.85933.20861.78921.7913

picture of methylcyclopropane state 1 conformation 1
More geometry information
Calculated Bond Angles
atom1 atom2 atom3 angle atom1 atom2 atom3 angle
C1 C2 H10 110.236 C1 C2 H11 110.917
C1 C2 H12 110.917 C1 C4 H5 59.833
C1 C4 H6 118.455 C1 C4 H8 117.396
C1 H5 C4 59.833 C1 H5 H7 118.455
C1 H5 H9 117.396 C2 C1 C3 114.895
C2 C1 C4 119.905 C2 C1 H5 119.905
C3 C1 C4 115.520 C3 C1 H5 115.520
C4 C1 H5 60.334 C4 H5 H7 117.716
C4 H5 H9 117.464 H5 C4 H6 117.716
H5 C4 H8 117.464 H6 C4 H8 114.992
H7 H5 H9 114.992 H10 C2 H11 108.146
H10 C2 H12 108.146 H11 C2 H12 108.382
Electronic energy levels
Charges, Dipole, Quadrupole and Polarizability