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All results from a given calculation for C2H2 (Acetylene)

using model chemistry: wB97X-D/daug-cc-pVDZ

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 wB97X-D/daug-cc-pVDZ
 hartrees
Energy at 0K-77.304341
Energy at 298.15K-77.304436
HF Energy-77.304341
Nuclear repulsion energy24.659549
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 wB97X-D/daug-cc-pVDZ
Mode Number Symmetry Frequency
(cm-1)
Scaled Frequency
(cm-1)
IR Intensities
(km mol-1)
Raman Act
4/u)
Dep P Dep U
1 Σg 3528 3528 0.00 50.28 0.29 0.45
2 Σg 2085 2085 0.00 123.97 0.06 0.11
3 Σu 3414 3414 91.41 0.00 0.00 0.00
4 Πg 600 600 0.00 3.12 0.75 0.86
4 Πg 600 600 0.00 3.12 0.75 0.86
5 Πu 747 747 103.23 0.00 0.00 0.00
5 Πu 747 747 103.23 0.00 0.00 0.00

Unscaled Zero Point Vibrational Energy (zpe) 5860.0 cm-1
Scaled (by 1) Zero Point Vibrational Energy (zpe) 5860.0 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 wB97X-D/daug-cc-pVDZ
B
1.17135

See section I.F.4 to change rotational constant units
Geometric Data calculated at wB97X-D/daug-cc-pVDZ

Point Group is D∞h

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
C1 0.000 0.000 0.604
C2 0.000 0.000 -0.604
H3 0.000 0.000 1.674
H4 0.000 0.000 -1.674

Atom - Atom Distances (Å)
  C1 C2 H3 H4
C11.20711.07062.2777
C21.20712.27771.0706
H31.07062.27773.3483
H42.27771.07063.3483

picture of Acetylene state 1 conformation 1
More geometry information
Calculated Bond Angles
atom1 atom2 atom3 angle atom1 atom2 atom3 angle
C1 C2 H4 180.000 C2 C1 H3 180.000
Electronic energy levels
Charges, Dipole, Quadrupole and Polarizability
Charges from optimized geometry at wB97X-D/daug-cc-pVDZ Charges (e)
Number Element Mulliken CHELPG AIM ESP
1 C 0.202      
2 C 0.202      
3 H -0.202      
4 H -0.202      


Electric dipole moments
Electric dipole components in Debye
(What's a Debye? See section VII.A.3)
  x y z Total
  0.000 0.000 0.000 0.000
CHELPG        
AIM        
ESP        


Electric Quadrupole moment
Quadrupole components in D Å
Primitive
 xyz
x -13.758 0.000 0.000
y 0.000 -13.758 0.000
z 0.000 0.000 -6.848
Traceless
 xyz
x -3.455 0.000 0.000
y 0.000 -3.455 0.000
z 0.000 0.000 6.911
Polar
3z2-r213.821
x2-y20.000
xy0.000
xz0.000
yz0.000


Polarizabilities
Components of the polarizability tensor.
Units are Å3 (Angstrom cubed)
Change units.
  x y z
x 2.959 0.000 0.000
y 0.000 2.959 0.000
z 0.000 0.000 4.727


<r2> (average value of r2) Å2
<r2> 17.131
(<r2>)1/2 4.139