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All results from a given calculation for C4H2 (Diacetylene)

using model chemistry: MP4/aug-cc-pVTZ

19 10 17 12 22

States and conformations

State Conformation minimum conformation conformer description state description
1 1 yes D*H 1Σg
Energy calculated at MP4/aug-cc-pVTZ
 hartrees
Energy at 0K-153.211876
Energy at 298.15K 
HF Energy-152.548612
Nuclear repulsion energy76.572864
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 MP4/aug-cc-pVTZ
Rotational Constants (cm-1) from geometry optimized at MP4/aug-cc-pVTZ
B
0.14452

See section I.F.4 to change rotational constant units
Geometric Data calculated at MP4/aug-cc-pVTZ

Point Group is D∞h

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
C1 0.000 0.000 0.687
C2 0.000 0.000 -0.687
C3 0.000 0.000 1.909
C4 0.000 0.000 -1.909
H5 0.000 0.000 2.974
H6 0.000 0.000 -2.974

Atom - Atom Distances (Å)
  C1 C2 C3 C4 H5 H6
C11.37491.22172.59662.28633.6612
C21.37492.59661.22173.66122.2863
C31.22172.59663.81831.06464.8829
C42.59661.22173.81834.88291.0646
H52.28633.66121.06464.88295.9475
H63.66122.28634.88291.06465.9475

picture of Diacetylene state 1 conformation 1
More geometry information
Calculated Bond Angles
atom1 atom2 atom3 angle atom1 atom2 atom3 angle
C1 C2 C4 180.000 C1 C3 H5 180.000
C2 C1 C3 180.000 C2 C4 H6 180.000
Electronic energy levels
Charges, Dipole, Quadrupole and Polarizability