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All results from a given calculation for C5H6 (1-Buten-3-yne, 2-methyl-)

using model chemistry: MP2/3-21G*

19 10 17 12 22

States and conformations

State Conformation minimum conformation conformer description state description
1 1 yes CS 1A'
Energy calculated at MP2/3-21G*
 hartrees
Energy at 0K-192.127698
Energy at 298.15K-192.132166
HF Energy-191.674245
Nuclear repulsion energy141.558527
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 MP2/3-21G*
Mode Number Symmetry Frequency
(cm-1)
Scaled Frequency
(cm-1)
IR Intensities
(km mol-1)
Raman Act
4/u)
Dep P Dep U
1 A' 3484 3314 45.82      
2 A' 3262 3103 9.66      
3 A' 3173 3018 4.00      
4 A' 3164 3010 12.64      
5 A' 3084 2934 11.96      
6 A' 2123 2020 1.62      
7 A' 1671 1589 5.41      
8 A' 1595 1518 10.70      
9 A' 1505 1431 0.14      
10 A' 1488 1415 3.52      
11 A' 1295 1232 14.98      
12 A' 1089 1036 3.11      
13 A' 970 923 0.14      
14 A' 749 712 1.45      
15 A' 672 640 43.17      
16 A' 580 551 9.53      
17 A' 410 390 0.02      
18 A' 188 179 1.42      
19 A" 3156 3002 12.68      
20 A" 1581 1504 6.88      
21 A" 1133 1078 1.10      
22 A" 920 875 52.00      
23 A" 754 718 2.99      
24 A" 597 568 31.89      
25 A" 518 493 16.77      
26 A" 236 224 4.42      
27 A" 175 166 0.00      

Unscaled Zero Point Vibrational Energy (zpe) 19785.1 cm-1
Scaled (by 0.9513) Zero Point Vibrational Energy (zpe) 18821.5 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 MP2/3-21G*
ABC
0.30842 0.13063 0.09338

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

Point Group is Cs

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
C1 -1.483 0.818 0.000
H2 -1.594 1.907 0.000
H3 -1.976 0.409 0.889
H4 -1.976 0.409 -0.889
C5 0.539 -2.172 0.000
H6 0.743 -3.216 0.000
C7 0.298 -0.970 0.000
C8 0.000 0.447 0.000
C9 0.983 1.371 0.000
H10 2.033 1.093 0.000
H11 0.750 2.433 0.000

Atom - Atom Distances (Å)
  C1 H2 H3 H4 C5 H6 C7 C8 C9 H10 H11
C11.09511.09541.09543.60904.60762.52391.52872.52703.52632.7555
H21.09511.78341.78344.60305.63163.44402.16212.63183.71682.4020
H31.09541.78341.77783.71114.61792.80412.16673.23534.16213.5090
H41.09541.78341.77783.71114.61792.80412.16673.23534.16213.5090
C53.60904.60303.71113.71111.06451.22542.67323.57083.59064.6093
H64.60765.63164.61794.61791.06452.28993.73764.59414.49875.6492
C72.52393.44402.80412.80411.22542.28991.44782.43952.69553.4327
C81.52872.16212.16672.16672.67323.73761.44781.34942.13302.1230
C92.52702.63183.23533.23533.57084.59412.43951.34941.08601.0867
H103.52633.71684.16214.16213.59064.49872.69552.13301.08601.8546
H112.75552.40203.50903.50904.60935.64923.43272.12301.08671.8546

picture of 1-Buten-3-yne, 2-methyl- state 1 conformation 1
More geometry information
Calculated Bond Angles
atom1 atom2 atom3 angle atom1 atom2 atom3 angle
C1 C8 C7 115.947 C1 C8 C9 122.685
H2 C1 H3 109.006 H2 C1 H4 109.006
H2 C1 C8 109.874 H3 C1 H4 108.482
H3 C1 C8 110.219 H4 C1 C8 110.219
C5 C7 C8 179.420 H6 C5 C7 179.745
C7 C8 C9 121.368 C8 C9 H10 121.911
C8 C9 H11 120.884 H10 C9 H11 117.205
Electronic energy levels

Electronic state

Charges, Dipole, Quadrupole and Polarizability