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All results from a given calculation for C5H4N4 (purine)

using model chemistry: MP2/6-31G(2df,p)

19 10 17 12 22

States and conformations

State Conformation minimum conformation conformer description state description
1 1 yes CS 1A
Energy calculated at MP2/6-31G(2df,p)
 hartrees
Energy at 0K-410.999552
Energy at 298.15K-411.007445
HF Energy-409.506234
Nuclear repulsion energy412.602107
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 MP2/6-31G(2df,p)
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' 3697 3492 121.65      
2 A' 3296 3113 0.11      
3 A' 3239 3059 10.45      
4 A' 3224 3045 6.52      
5 A' 1656 1564 43.57      
6 A' 1625 1535 32.01      
7 A' 1509 1425 20.81      
8 A' 1495 1412 14.54      
9 A' 1446 1366 58.08      
10 A' 1427 1348 15.38      
11 A' 1408 1329 65.56      
12 A' 1352 1277 36.02      
13 A' 1329 1255 10.95      
14 A' 1286 1214 26.66      
15 A' 1207 1140 6.29      
16 A' 1130 1067 7.53      
17 A' 1105 1044 6.11      
18 A' 941 889 0.64      
19 A' 914 863 12.79      
20 A' 803 758 12.84      
21 A' 654 618 0.87      
22 A' 565 533 4.60      
23 A' 440 416 13.55      
24 A" 993 938 0.53      
25 A" 938 886 10.28      
26 A" 882 833 6.12      
27 A" 813 768 5.30      
28 A" 672 634 2.04      
29 A" 631 596 31.56      
30 A" 547 517 90.54      
31 A" 425 401 2.05      
32 A" 247 233 0.88      
33 A" 235 222 3.64      

Unscaled Zero Point Vibrational Energy (zpe) 21064.8 cm-1
Scaled (by 0.9445) Zero Point Vibrational Energy (zpe) 19895.7 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 MP2/6-31G(2df,p)
ABC
0.13741 0.05879 0.04117

See section I.F.4 to change rotational constant units
Geometric Data calculated at MP2/6-31G(2df,p)

Point Group is Cs

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
N1 -1.811 -1.261 0.000
C2 -2.099 0.063 0.000
N3 -1.271 1.104 0.000
C4 0.000 0.704 0.000
C5 0.454 -0.626 0.000
C6 -0.532 -1.613 0.000
N7 1.832 -0.693 0.000
C8 2.174 0.578 0.000
N9 1.124 1.470 0.000
H10 -3.155 0.299 0.000
H11 -0.303 -2.673 0.000
H12 3.198 0.917 0.000
H13 1.165 2.477 0.000

Atom - Atom Distances (Å)
  N1 C2 N3 C4 C5 C6 N7 C8 N9 H10 H11 H12 H13
N11.35592.42572.67262.35221.32623.68674.38934.00922.05982.06555.46164.7782
C21.35591.32952.19492.64502.29514.00314.30463.51671.08193.27355.36534.0597
N32.42571.32951.33242.44322.81553.58533.48532.42282.04853.89904.47272.7967
C42.67262.19491.33241.40602.37782.30362.17801.36003.18113.39123.20472.1214
C52.35222.64502.44321.40601.39511.37932.10032.20123.72612.18253.14793.1840
C61.32622.29512.81552.37781.39512.53683.48263.50013.24621.08464.50694.4285
N73.68674.00313.58532.30361.37932.53681.31652.27615.08462.91232.11103.2393
C84.38934.30463.48532.17802.10033.48261.31651.37825.33684.08821.07782.1504
N94.00923.51672.42281.36002.20123.50012.27611.37824.43634.38262.14661.0076
H102.05981.08192.04853.18113.72613.24625.08465.33684.43634.11946.38284.8381
H112.06553.27353.89903.39122.18251.08462.91234.08824.38264.11945.01465.3557
H125.46165.36534.47273.20473.14794.50692.11101.07782.14666.38285.01462.5625
H134.77824.05972.79672.12143.18404.42853.23932.15041.00764.83815.35572.5625

picture of purine state 1 conformation 1
More geometry information
Calculated Bond Angles
atom1 atom2 atom3 angle atom1 atom2 atom3 angle
N1 C2 N3 129.185 N1 C2 H10 114.872
N1 C6 C5 119.598 N1 C6 H11 117.564
C2 N1 C6 117.672 C2 N3 C4 111.090
N3 C2 H10 115.943 N3 C4 C5 126.280
N3 C4 N9 128.272 C4 C5 C6 116.176
C4 C5 N7 111.594 C4 N9 C8 105.380
C4 N9 H13 126.635 C5 C4 N9 105.448
C5 C6 H11 122.839 C5 N7 C8 102.331
C6 C5 N7 132.230 N7 C8 N9 115.246
N7 C8 H12 123.383 C8 N9 H13 127.985
N9 C8 H12 121.371
Electronic energy levels
Charges, Dipole, Quadrupole and Polarizability