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

using model chemistry: B3LYP/3-21G

19 10 17 12 22

States and conformations

State Conformation minimum conformation conformer description state description
1 1 yes C3V 1A1
Energy calculated at B3LYP/3-21G
 hartrees
Energy at 0K-157.605208
Energy at 298.15K-157.615927
HF Energy-157.605208
Nuclear repulsion energy133.825094
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 B3LYP/3-21G
Mode Number Symmetry Frequency
(cm-1)
Scaled Frequency
(cm-1)
IR Intensities
(km mol-1)
Raman Act
(Å4/u)
Dep P Dep U
1 A1 3111 3002 91.60      
2 A1 3043 2937 10.14      
3 A1 3037 2930 4.93      
4 A1 1578 1522 19.74      
5 A1 1474 1422 4.13      
6 A1 1244 1201 1.81      
7 A1 791 763 1.00      
8 A1 437 422 0.56      
9 A2 3102 2993 0.00      
10 A2 1548 1493 0.00      
11 A2 993 958 0.00      
12 A2 220 213 0.00      
13 E 3107 2998 52.53      
13 E 3107 2998 52.55      
14 E 3098 2989 2.85      
14 E 3098 2989 2.85      
15 E 3036 2929 28.37      
15 E 3036 2929 28.38      
16 E 1572 1517 5.28      
16 E 1572 1517 5.28      
17 E 1554 1499 0.57      
17 E 1554 1499 0.57      
18 E 1447 1397 8.13      
18 E 1447 1397 8.13      
19 E 1387 1338 4.82      
19 E 1387 1338 4.82      
20 E 1213 1170 4.76      
20 E 1213 1170 4.76      
21 E 988 953 0.54      
21 E 988 953 0.54      
22 E 944 911 2.16      
22 E 944 911 2.16      
23 E 365 353 0.02      
23 E 365 353 0.02      
24 E 259 250 0.01      
24 E 259 250 0.01      

Unscaled Zero Point Vibrational Energy (zpe) 29258.3 cm-1
Scaled (by 0.9649) Zero Point Vibrational Energy (zpe) 28231.3 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 B3LYP/3-21G
ABC
0.25695 0.25695 0.14925

See section I.F.4 to change rotational constant units
Geometric Data calculated at B3LYP/3-21G

Point Group is C3v

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
C1 0.000 0.000 0.389
H2 0.000 0.000 1.488
C3 0.000 1.465 -0.099
C4 1.269 -0.733 -0.099
C5 -1.269 -0.733 -0.099
H6 0.000 1.495 -1.196
H7 1.294 -0.747 -1.196
H8 -1.294 -0.747 -1.196
H9 0.889 1.997 0.259
H10 -0.889 1.997 0.259
H11 1.285 -1.769 0.259
H12 2.174 -0.229 0.259
H13 -2.174 -0.229 0.259
H14 -1.285 -1.769 0.259

Atom - Atom Distances (Å)
  C1 H2 C3 C4 C5 H6 H7 H8 H9 H10 H11 H12 H13 H14
C11.09871.54461.54461.54462.17892.17892.17892.19022.19022.19022.19022.19022.1902
H21.09872.16032.16032.16033.07233.07233.07232.50822.50822.50822.50822.50822.5082
C31.54462.16032.53792.53791.09722.78822.78821.09631.09633.49832.77942.77943.4983
C41.54462.16032.53792.53792.78821.09722.78822.77943.49831.09631.09633.49832.7794
C51.54462.16032.53792.53792.78822.78821.09723.49832.77942.77943.49831.09631.0963
H62.17893.07231.09722.78822.78822.58892.58891.77761.77763.79713.13273.13273.7971
H72.17893.07232.78821.09722.78822.58892.58893.13273.79711.77761.77763.79713.1327
H82.17893.07232.78822.78821.09722.58892.58893.79713.13273.13273.79711.77761.7776
H92.19022.50821.09632.77943.49831.77763.13273.79711.77823.78672.57033.78674.3485
H102.19022.50821.09633.49832.77941.77763.79713.13271.77824.34853.78672.57033.7867
H112.19022.50823.49831.09632.77943.79711.77763.13273.78674.34851.77823.78672.5703
H122.19022.50822.77941.09633.49833.13271.77763.79712.57033.78671.77824.34853.7867
H132.19022.50822.77943.49831.09633.13273.79711.77763.78672.57033.78674.34851.7782
H142.19022.50823.49832.77941.09633.79713.13271.77764.34853.78672.57033.78671.7782

picture of Isobutane state 1 conformation 1
More geometry information
Calculated Bond Angles
atom1 atom2 atom3 angle atom1 atom2 atom3 angle
C1 C3 H6 109.978 C1 C3 H9 110.920
C1 C3 H10 110.920 C1 C4 H7 109.978
C1 C4 H11 110.920 C1 C4 H12 110.919
C1 C5 H8 109.978 C1 C5 H13 110.919
C1 C5 H14 110.920 H2 C1 C3 108.442
H2 C1 C4 108.442 H2 C1 C5 108.442
C3 C1 C4 110.481 C3 C1 C5 110.481
C4 C1 C5 110.481 H6 C3 H9 108.271
H6 C3 H10 108.271 H7 C4 H11 108.271
H7 C4 H12 108.271 H8 C5 H13 108.271
H8 C5 H14 108.271 H9 C3 H10 108.394
H11 C4 H12 108.394 H13 C5 H14 108.394
Electronic energy levels

Electronic state

Charges, Dipole, Quadrupole and Polarizability
Charges from optimized geometry at B3LYP/3-21G Charges (e)
Number Element Mulliken CHELPG AIM ESP
1 C -0.255      
2 H 0.188      
3 C -0.523      
4 C -0.523      
5 C -0.523      
6 H 0.181      
7 H 0.181      
8 H 0.181      
9 H 0.182      
10 H 0.182      
11 H 0.182      
12 H 0.182      
13 H 0.182      
14 H 0.182      


Electric dipole moments
Electric dipole components in Debye
(What's a Debye? See section VII.A.3)
  x y z Total
  0.000 0.000 0.053 0.053
CHELPG        
AIM        
ESP 0.004 0.001 -0.033 0.033


Electric Quadrupole moment
Quadrupole components in D Å
Primitive
 xyz
x -28.435 0.000 0.000
y 0.000 -28.435 0.000
z 0.000 0.000 -28.092
Traceless
 xyz
x -0.171 0.000 0.000
y 0.000 -0.171 0.000
z 0.000 0.000 0.343
Polar
3z2-r20.686
x2-y20.000
xy0.000
xz0.000
yz0.000


Polarizabilities
Components of the polarizability tensor.
Units are Å3 (Angstrom cubed)
Change units.
  x y z
x 6.349 0.000 0.000
y 0.000 6.349 0.000
z 0.000 0.000 5.696


<r2> (average value of r2) Å2
<r2> 99.710
(<r2>)1/2 9.985