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All results from a given calculation for C6H2 (hexatriyne)

using model chemistry: QCISD/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 QCISD/3-21G*
 hartrees
Energy at 0K-227.469551
Energy at 298.15K 
HF Energy-226.907470
Nuclear repulsion energy142.073678
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/3-21G*
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 3419 3286 0.00      
2 Σg 2336 2245 0.00      
3 Σg 2072 1991 0.00      
4 Σg 598 575 0.00      
5 Σu 3419 3286 138.40      
6 Σu 2180 2095 1.18      
7 Σu 1120 1077 1.18      
8 Πg 571 549 0.00      
8 Πg 571 549 0.00      
9 Πg 146 141 0.00      
9 Πg 146 141 0.00      
10 Πg 1160i 1115i 0.00      
10 Πg 1160i 1115i 0.00      
11 Πu 568 546 86.87      
11 Πu 568 546 86.87      
12 Πu 102 98 4.23      
12 Πu 102 98 4.23      
13 Πu 466i 448i 11.52      
13 Πu 466i 448i 11.52      

Unscaled Zero Point Vibrational Energy (zpe) 7333.0 cm-1
Scaled (by 0.9611) Zero Point Vibrational Energy (zpe) 7047.8 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/3-21G*
B
0.04316

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

Point Group is D∞h

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
C1 0.000 0.000 0.612
C2 0.000 0.000 -0.612
C3 0.000 0.000 1.998
C4 0.000 0.000 -1.998
C5 0.000 0.000 3.220
C6 0.000 0.000 -3.220
H7 0.000 0.000 4.289
H8 0.000 0.000 -4.289

Atom - Atom Distances (Å)
  C1 C2 C3 C4 C5 C6 H7 H8
C11.22371.38572.60942.60783.83153.67724.9010
C21.22372.60941.38573.83152.60784.90103.6772
C31.38572.60943.99501.22225.21722.29166.2866
C42.60941.38573.99505.21721.22226.28662.2916
C52.60783.83151.22225.21726.43941.06947.5088
C63.83152.60785.21721.22226.43947.50881.0694
H73.67724.90102.29166.28661.06947.50888.5782
H84.90103.67726.28662.29167.50881.06948.5782

picture of hexatriyne 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 C5 180.000
C2 C1 C3 180.000 C2 C4 C6 180.000
C3 C5 H7 180.000 C4 C6 H8 180.000
Electronic energy levels
Charges, Dipole, Quadrupole and Polarizability