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All results from a given calculation for CH2CH(CH3)2 (Isobutyl radical)

using model chemistry: MP2/3-21G

19 10 17 12 22

States and conformations

State Conformation minimum conformation conformer description state description
1 1 yes C1 2A'
Energy calculated at MP2/3-21G
 hartrees
Energy at 0K-156.150424
Energy at 298.15K-156.159256
HF Energy-155.802137
Nuclear repulsion energy125.519416
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 MP2/3-21G
Mode Number Symmetry Frequency
(cm-1)
Scaled Frequency
(cm-1)
IR Intensities
(km mol-1)
Raman Act
4/u)
Dep P Dep U
1 A 3178 3033 15.18      
2 A 3158 3015 48.83      
3 A 3152 3008 35.87      
4 A 3077 2937 10.75      
5 A 3017 2880 20.43      
6 A 1610 1536 9.08      
7 A 1604 1531 4.79      
8 A 1544 1474 0.37      
9 A 1492 1424 4.04      
10 A 1386 1323 2.27      
11 A 1250 1193 2.30      
12 A 1154 1102 2.12      
13 A 990 945 1.21      
14 A 809 772 0.03      
15 A 523 500 20.28      
16 A 408 389 20.51      
17 A 377 359 1.12      
18 A 271 259 0.18      
19 A 3288 3138 16.51      
20 A 3154 3010 3.61      
21 A 3149 3006 13.98      
22 A 3075 2936 26.00      
23 A 1594 1522 2.77      
24 A 1592 1519 0.29      
25 A 1478 1411 5.82      
26 A 1398 1334 0.88      
27 A 1216 1161 0.69      
28 A 1008 962 0.02      
29 A 1001 956 1.65      
30 A 936 894 0.86      
31 A 386 369 0.01      
32 A 248 237 0.00      
33 A 135 129 0.49      

Unscaled Zero Point Vibrational Energy (zpe) 26328.8 cm-1
Scaled (by 0.9545) Zero Point Vibrational Energy (zpe) 25130.8 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 MP2/3-21G
ABC
0.27602 0.26112 0.15249

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

Point Group is Cs

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
C1 0.000 0.377 0.000
C2 1.491 0.124 0.000
H3 -0.185 1.465 0.000
H4 2.051 0.151 0.929
H5 2.051 0.151 -0.929
C6 -0.661 -0.216 -1.275
C7 -0.661 -0.216 1.275
H8 -0.518 -1.302 -1.292
H9 -1.736 -0.001 -1.283
H10 -0.212 0.211 -2.179
H11 -0.518 -1.302 1.292
H12 -1.736 -0.001 1.283
H13 -0.212 0.211 2.179

Atom - Atom Distances (Å)
  C1 C2 H3 H4 H5 C6 C7 H8 H9 H10 H11 H12 H13
C11.51221.10352.26282.26281.55371.55372.18092.19152.19552.18092.19152.1955
C21.51222.14631.08521.08522.52432.52432.78183.47472.76672.78183.47472.7667
H31.10352.14632.75492.75492.16252.16253.07162.49022.51403.07162.49022.5140
H42.26281.08522.75491.85863.51382.75823.69374.38823.84502.97313.80602.5854
H52.26281.08522.75491.85862.75823.51382.97313.80602.58543.69374.38823.8450
C61.55372.52432.16253.51382.75822.55011.09551.09591.09602.79132.78333.5092
C71.55372.52432.16252.75823.51382.55012.79132.78333.50921.09551.09591.0960
H82.18092.78183.07163.69372.97311.09552.79131.78151.78012.58473.13183.7991
H92.19153.47472.49024.38823.80601.09592.78331.78151.78043.13182.56683.7889
H102.19552.76672.51403.84502.58541.09603.50921.78011.78043.79913.78894.3580
H112.18092.78183.07162.97313.69372.79131.09552.58473.13183.79911.78151.7801
H122.19153.47472.49023.80604.38822.78331.09593.13182.56683.78891.78151.7804
H132.19552.76672.51402.58543.84503.50921.09603.79913.78894.35801.78011.7804

picture of Isobutyl radical state 1 conformation 1
More geometry information
Calculated Bond Angles
atom1 atom2 atom3 angle atom1 atom2 atom3 angle
C1 C2 H4 120.298 C1 C2 H5 120.298
C1 C6 H8 109.606 C1 C6 H9 110.415
C1 C6 H10 110.723 C1 C7 H11 109.606
C1 C7 H12 110.415 C1 C7 H13 110.723
C2 C1 H3 109.283 C2 C1 C6 110.831
C2 C1 C7 110.831 H3 C1 C6 107.743
H3 C1 C7 107.743 H4 C2 H5 117.810
C6 C1 C7 110.302 H8 C6 H9 108.775
H8 C6 H10 108.638 H9 C6 H10 108.636
H11 C7 H12 108.775 H11 C7 H13 108.638
H12 C7 H13 108.636
Electronic energy levels

Electronic state

Charges, Dipole, Quadrupole and Polarizability
Charges from optimized geometry at MP2/3-21G Charges (e)
Number Element Mulliken CHELPG AIM ESP
1 C -0.315     0.465
2 C -0.306     -0.494
3 H 0.199     -0.038
4 H 0.174     0.156
5 H 0.174     0.156
6 C -0.501     -0.439
7 C -0.501     -0.439
8 H 0.183     0.116
9 H 0.178     0.098
10 H 0.178     0.102
11 H 0.183     0.116
12 H 0.178     0.098
13 H 0.178     0.102


Electric dipole moments
Electric dipole components in Debye
(What's a Debye? See section VII.A.3)
  x y z Total
  -0.086 0.182 0.000 0.201
CHELPG        
AIM        
ESP -0.081 0.172 0.000 0.190


Electric Quadrupole moment
Quadrupole components in D Å
Primitive
 xyz
x -28.059 0.046 0.000
y 0.046 -28.850 0.000
z 0.000 0.000 -27.942
Traceless
 xyz
x 0.337 0.046 0.000
y 0.046 -0.849 0.000
z 0.000 0.000 0.512
Polar
3z2-r21.023
x2-y20.791
xy0.046
xz0.000
yz0.000


Polarizabilities
Components of the polarizability tensor.
Units are Å3 (Angstrom cubed)
Change units.
  x y z
x 6.128 -0.024 0.000
y -0.024 4.772 0.000
z 0.000 0.000 6.111


<r2> (average value of r2) Å2
<r2> 95.778
(<r2>)1/2 9.787