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All results from a given calculation for HCOOHH2O (Formic acid water dimer)

using model chemistry: MP2/6-31G*

19 10 17 12 22

States and conformations

State Conformation minimum conformation conformer description state description
1 1 yes C1 1A
Energy calculated at MP2/6-31G*
 hartrees
Energy at 0K-265.461467
Energy at 298.15K-265.466514
HF Energy-264.784634
Counterpoise corrected energy-265.454463
CP Energy at 298.15K-265.459215
Counterpoise optimized geometry corrected energy 
CP opt. Energy at 298.15K 
Nuclear repulsion energy123.622154
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*
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 3854 3634 99.10      
2 A 3666 3457 158.16      
3 A 3319 3130 564.51      
4 A 3162 2982 96.65      
5 A 1808 1705 260.71      
6 A 1744 1644 141.06      
7 A 1504 1418 1.41      
8 A 1430 1348 12.31      
9 A 1252 1181 218.42      
10 A 1093 1031 26.90      
11 A 981 925 152.03      
12 A 723 682 162.39      
13 A 654 617 173.89      
14 A 382 360 101.10      
15 A 303 286 80.76      
16 A 250 236 41.29      
17 A 202 190 26.46      
18 A 197 186 7.88      

Unscaled Zero Point Vibrational Energy (zpe) 13261.3 cm-1
Scaled (by 0.943) Zero Point Vibrational Energy (zpe) 12505.4 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*
ABC
0.38478 0.16593 0.11707

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

Point Group is C1

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
H1 0.395 0.979 0.033
O2 -0.589 1.140 0.013
O3 1.886 0.032 -0.076
C4 -1.191 -0.048 -0.003
O5 -0.648 -1.145 0.023
H6 -2.279 0.080 -0.040
H7 2.483 -0.226 0.642
H8 1.357 -0.760 -0.294

Atom - Atom Distances (Å)
  H1 O2 O3 C4 O5 H6 H7 H8
H10.99741.76921.89032.36692.82292.48652.0140
O20.99742.71271.33222.28641.99643.42042.7368
O31.76922.71273.07862.79524.16540.96860.9770
C41.89031.33223.07861.22491.09643.73472.6614
O52.36692.28642.79521.22492.04153.32132.0656
H62.82291.99644.16541.09642.04154.82083.7406
H72.48653.42040.96863.73473.32134.82081.5589
H82.01402.73680.97702.66142.06563.74061.5589

picture of Formic acid water dimer state 1 conformation 1
More geometry information
Calculated Bond Angles
atom1 atom2 atom3 angle atom1 atom2 atom3 angle
H1 O2 C4 107.603 H1 O3 H7 128.097
H1 O3 H8 89.529 O2 H1 O3 156.392
O2 C4 O5 126.744 O2 C4 H6 110.202
O5 C4 H6 123.053 H7 O3 H8 106.497
Electronic energy levels
Charges, Dipole, Quadrupole and Polarizability