return to home page Computational Chemistry Comparison and Benchmark DataBase Release 22 (May 2022) Standard Reference Database 101 National Institute of Standards and Technology
You are here: Calculated > Energy > Optimized > Energy

All results from a given calculation for C2F2 (difluoroacetylene)

using model chemistry: MP2=FULL/3-21G*

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 MP2=FULL/3-21G*
 hartrees
Energy at 0K-273.404321
Energy at 298.15K-273.403058
HF Energy-272.974168
Nuclear repulsion energy92.691896
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=FULL/3-21G*
Mode Number Symmetry Frequency
(cm-1)
Scaled Frequency
(cm-1)
IR Intensities
(km mol-1)
Raman Act
(Å4/u)
Dep P Dep U
1 Σg 2512 2381 0.00      
2 Σg 772 731 0.00      
3 Σu 1367 1295 159.11      
4 Πg 263 249 0.00      
4 Πg 263 249 0.00      
5 Πu 274 260 1.19      
5 Πu 274 260 1.19      

Unscaled Zero Point Vibrational Energy (zpe) 2861.5 cm-1
Scaled (by 0.948) Zero Point Vibrational Energy (zpe) 2712.7 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=FULL/3-21G*
B
0.11260

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

Point Group is D∞h

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
C1 0.000 0.000 0.600
C2 0.000 0.000 -0.600
F3 0.000 0.000 1.927
F4 0.000 0.000 -1.927

Atom - Atom Distances (Å)
  C1 C2 F3 F4
C11.20101.32622.5272
C21.20102.52721.3262
F31.32622.52723.8535
F42.52721.32623.8535

picture of difluoroacetylene state 1 conformation 1
More geometry information
Calculated Bond Angles
atom1 atom2 atom3 angle atom1 atom2 atom3 angle
C1 C2 F4 180.000 C2 C1 F3 180.000
Electronic energy levels
Charges, Dipole, Quadrupole and Polarizability
Charges from optimized geometry at MP2=FULL/3-21G* Charges (e)
Number Element Mulliken CHELPG AIM ESP
1 C 0.350      
2 C 0.350      
3 F -0.350      
4 F -0.350      


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