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All results from a given calculation for CH3CH(CH3)CH3 (Isobutane)

using model chemistry: G2

19 10 17 12 22

States and conformations

State Conformation minimum conformation conformer description state description
1 1 yes C3V 1A1
Energy calculated at G2
 hartrees
Energy at 0K-158.084302
Energy at 298.15K-158.077497
HF Energy-157.298978
Nuclear repulsion energy134.814598
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 HF/6-31G*
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 3261 3072 150.77      
2 A1 3199 3014 12.13      
3 A1 3180 2996 21.37      
4 A1 1660 1564 12.12      
5 A1 1581 1489 2.35      
6 A1 1326 1249 0.02      
7 A1 849 800 0.31      
8 A1 464 437 0.09      
9 A2 3254 3066 0.00      
10 A2 1629 1535 0.00      
11 A2 1044 984 0.00      
12 A2 228 214 0.00      
13 E 3260 3072 86.33      
13 E 3260 3072 86.33      
14 E 3247 3060 5.77      
14 E 3247 3060 5.77      
15 E 3189 3005 41.61      
15 E 3189 3005 41.61      
16 E 1652 1557 2.11      
16 E 1652 1557 2.11      
17 E 1635 1540 0.25      
17 E 1635 1540 0.25      
18 E 1557 1467 4.62      
18 E 1557 1467 4.62      
19 E 1494 1408 3.39      
19 E 1494 1408 3.39      
20 E 1300 1225 2.04      
20 E 1300 1225 2.04      
21 E 1048 987 0.00      
21 E 1048 987 0.00      
22 E 1006 948 0.57      
22 E 1006 948 0.57      
23 E 391 368 0.02      
23 E 391 368 0.02      
24 E 280 263 0.00      
24 E 280 263 0.00      

Unscaled Zero Point Vibrational Energy (zpe) 30895.0 cm-1
Scaled (by 0.9422) Zero Point Vibrational Energy (zpe) 29109.3 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=FULL/6-31G*
ABC
0.26166 0.26166 0.15189

See section I.F.4 to change rotational constant units
Geometric Data calculated at MP2=FULL/6-31G*

Point Group is C3v

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
C1 0.000 0.000 0.377
H2 0.000 0.000 1.475
C3 0.000 1.450 -0.096
C4 1.256 -0.725 -0.096
C5 -1.256 -0.725 -0.096
H6 0.000 1.493 -1.191
H7 1.293 -0.747 -1.191
H8 -1.293 -0.747 -1.191
H9 0.886 1.984 0.261
H10 -0.886 1.984 0.261
H11 1.276 -1.759 0.261
H12 2.161 -0.225 0.261
H13 -2.161 -0.225 0.261
H14 -1.276 -1.759 0.261

Atom - Atom Distances (Å)
  C1 H2 C3 C4 C5 H6 H7 H8 H9 H10 H11 H12 H13 H14
C11.09821.52541.52541.52542.16542.16542.16542.17592.17592.17592.17592.17592.1759
H21.09822.13842.13842.13843.05603.05603.05602.48902.48902.48902.48902.48902.4890
C31.52542.13842.51162.51161.09542.77432.77431.09431.09433.47182.75772.75773.4718
C41.52542.13842.51162.51162.77431.09542.77432.75773.47181.09431.09433.47182.7577
C51.52542.13842.51162.51162.77432.77431.09543.47182.75772.75773.47181.09431.0943
H62.16543.05601.09542.77432.77432.58662.58661.77031.77033.78343.11983.11983.7834
H72.16543.05602.77431.09542.77432.58662.58663.11983.78341.77031.77033.78343.1198
H82.16543.05602.77432.77431.09542.58662.58663.78343.11983.11983.78341.77031.7703
H92.17592.48901.09432.75773.47181.77033.11983.78341.77113.76352.55123.76354.3223
H102.17592.48901.09433.47182.75771.77033.78343.11981.77114.32233.76352.55123.7635
H112.17592.48903.47181.09432.75773.78341.77033.11983.76354.32231.77113.76352.5512
H122.17592.48902.75771.09433.47183.11981.77033.78342.55123.76351.77114.32233.7635
H132.17592.48902.75773.47181.09433.11983.78341.77033.76352.55123.76354.32231.7711
H142.17592.48903.47182.75771.09433.78343.11981.77034.32233.76352.55123.76351.7711

picture of Isobutane state 1 conformation 1
More geometry information
Calculated Bond Angles
atom1 atom2 atom3 angle atom1 atom2 atom3 angle
C1 C3 H6 110.932 C1 C3 H9 111.266
C1 C3 H10 111.266 C1 C4 H7 110.932
C1 C4 H11 111.266 C1 C4 H12 111.266
C1 C5 H8 110.932 C1 C5 H13 111.266
C1 C5 H14 111.266 H2 C1 C3 107.874
H2 C1 C4 107.874 H2 C1 C5 107.874
C3 C1 C4 111.020 C3 C1 C5 111.020
C4 C1 C5 111.020 H6 C3 H9 107.712
H6 C3 H10 107.712 H7 C4 H11 107.712
H7 C4 H12 107.712 H8 C5 H13 107.712
H8 C5 H14 107.712 H9 C3 H10 107.786
H11 C4 H12 107.786 H13 C5 H14 107.786
Electronic energy levels

Electronic state

Charges, Dipole, Quadrupole and Polarizability