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All results from a given calculation for C2F2 (difluoroacetylene)

using model chemistry: QCISD/6-31G

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 QCISD/6-31G
 hartrees
Energy at 0K-274.799440
Energy at 298.15K-274.797968
HF Energy-274.357571
Nuclear repulsion energy91.410716
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 QCISD/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 Ag 2440 2351 0.00      
2 Ag 719 692 0.00      
3 Ag 195 188 0.00      
4 Au 225 217 2.54      
5 Bu 1248 1202 124.03      
6 Bu 234 225 3.08      

Unscaled Zero Point Vibrational Energy (zpe) 2529.7 cm-1
Scaled (by 0.9636) Zero Point Vibrational Energy (zpe) 2437.6 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 QCISD/6-31G
ABC
142.43797 0.11003 0.10994

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

Point Group is C2h

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
C1 -0.055 0.603 0.000
C2 0.055 -0.603 0.000
F3 0.055 1.950 0.000
F4 -0.055 -1.950 0.000

Atom - Atom Distances (Å)
  C1 C2 F3 F4
C11.21131.35092.5526
C21.21132.55261.3509
F31.35092.55263.9006
F42.55261.35093.9006

picture of difluoroacetylene state 1 conformation 1
More geometry information
Calculated Bond Angles
atom1 atom2 atom3 angle atom1 atom2 atom3 angle
C1 C2 F4 170.076 C2 C1 F3 170.076
Electronic energy levels
Charges, Dipole, Quadrupole and Polarizability
Charges from optimized geometry at QCISD/6-31G Charges (e)
Number Element Mulliken CHELPG AIM ESP
1 C 0.362      
2 C 0.362      
3 F -0.362      
4 F -0.362      


Electric dipole moments


Electric Quadrupole moment
Quadrupole components in D Å


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


<r2> (average value of r2) Å2
<r2> 0.000
(<r2>)1/2 0.000