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Relative enthalpies of isomers - Comparison of 0K enthalpies (kJ mol-1)

Isomers of C4H4

17 10 10 15 39
index Species CAS number Name Relative experimental enthalpy (kJ mol-1) sketch
a C4H4 157391 Tetrahedrane   sketch of Tetrahedrane
b C2H3CCH 689974 1-Buten-3-yne   sketch of 1-Buten-3-yne
c C4H4 1120532 cyclobutadiene   sketch of cyclobutadiene
d H2CCCCH2 2873509 Butatriene   sketch of Butatriene
The calculated enthalpies include the calculated and scaled vibrational zero-point energy.
Methods with predefined basis sets
composite G1
NC
NC
NC
G2MP2
NC
NC
NC
G3 0.0 a
-107.2 c
G3B3 0.0 a
-253.2 b
-107.4 c
-223.0 d
CBS-Q 0.0 a
-104.3 c

Methods with standard basis sets
STO-3G 3-21G 3-21G* 6-31G 6-31G* 6-31G** 6-31+G** 6-311G* 6-311G** 6-31G(2df,p) 6-311+G(3df,2p) TZVP cc-pVDZ cc-pVTZ cc-pVQZ aug-cc-pVDZ aug-cc-pVTZ aug-cc-pVQZ cc-pV(T+d)Z daug-cc-pVTZ
hartree fock HF 0.0 a
-260.4 b
-105.8 c
-179.2 d
0.0 a
-388.3 b
-166.7 c
-346.4 d
0.0 a
-388.3 b
-166.7 c
-346.4 d
0.0 a
-386.3 b
-176.4 c
-345.9 d
0.0 a
-285.3 b
-109.5 c
-241.9 d
0.0 a
-281.2 b
-106.5 c
-237.7 d
0.0 a
-286.1 b
-110.4 c
-241.3 d
0.0 a
-297.9 b
-117.4 c
-253.2 d
0.0 a
-292.5 b
-111.9 c
-246.0 d
0.0 a
-282.7 b
-105.3 c
-240.7 d
0.0 a
-289.4 b
-244.4 d
0.0 a
-300.9 b
-115.6 c
-254.6 d
0.0 a
-285.5 b
-113.1 c
-242.1 d
0.0 a
-292.3 b
-111.7 c
-247.0 d
0.0 a
-111.9 c
0.0 a
-287.2 b
-116.2 c
-243.4 d
0.0 a
-292.5 b
-112.8 c
-247.3 d
0.0 a
-112.5 c

NC
NC
0.0 a
-292.4 b
-112.5 c
-247.2 d
density functional LSDA
NC
NC
NC

NC
NC
NC

NC
NC
NC

NC
NC
NC

NC
NC
NC

NC
NC
NC

NC
NC
NC

NC
NC
NC

NC
NC
NC

NC
NC
NC
   
NC
NC
NC

NC
NC
NC
 
NC
NC
NC
   
NC
NC
 
BLYP 0.0 a
-253.7 b
-137.1 c
-239.1 d
0.0 a
-348.8 b
-167.5 c
-346.0 d
0.0 a
-348.8 b
-167.5 c
-346.0 d
0.0 a
-340.2 b
-162.8 c
-340.2 d
0.0 a
-266.0 b
-109.9 c
-268.5 d
0.0 a
-263.0 b
-107.9 c
-264.8 d
0.0 a
-266.9 b
-109.0 c
-265.8 d
0.0 a
-283.7 b
-116.1 c
-282.4 d
0.0 a
-278.6 b
-111.7 c
-275.4 d
0.0 a
-267.3 b
-104.2 c
-269.2 d
  0.0 a
-113.2 c
0.0 a
-264.9 b
-110.9 c
-263.3 d
0.0 a
-279.8 b
-110.6 c
-276.9 d
  0.0 a
-267.1 b
-263.5 d
   
NC
NC
 
B1B95 0.0 a
-189.0 b
-82.7 c
-161.0 d
0.0 a
-288.2 b
-115.4 c
-275.7 d
0.0 a
-288.2 b
-115.4 c
0.0 a
-280.4 b
-114.3 c
-271.0 d
0.0 a
-181.4 b
-49.1 c
-172.7 d
0.0 a
-203.7 b
-49.1 c
-195.8 d
0.0 a
-186.5 b
-47.5 c
-176.4 d
0.0 a
-202.5 b
-55.7 c
-191.9 d
0.0 a
-196.7 b
-50.6 c
-184.5 d
0.0 a
-184.2 b
-43.2 c
-176.2 d
  0.0 a
-52.5 c
0.0 a
-184.5 b
-50.6 c
-174.5 d
0.0 a
-189.4 b
-48.8 c
  0.0 a
-181.3 b
-51.4 c
0.0 a
-188.9 b
-48.9 c
     
B3LYP 0.0 a
-240.6 b
-122.8 c
-213.1 d
0.0 a
-341.5 b
-157.5 c
-330.4 d
0.0 a
-341.5 b
-157.5 c
-330.4 d
0.0 a
-333.3 b
-155.9 c
-324.8 d
0.0 a
-251.6 b
-98.3 c
-245.0 d
0.0 a
-248.4 b
-96.1 c
-241.1 d
0.0 a
-252.3 b
-97.7 c
-242.6 d
0.0 a
-268.9 b
-104.9 c
-258.8 d
0.0 a
-263.6 b
-100.1 c
-251.7 d
0.0 a
-252.3 b
-92.4 c
-245.4 d
0.0 a
-261.1 b
-249.6 d
0.0 a
-268.8 b
-102.0 c
-257.0 d
0.0 a
-250.8 b
-99.8 c
-240.8 d
0.0 a
-264.3 b
-98.9 c
-252.8 d
0.0 a
-98.1 c
0.0 a
-253.5 b
-100.5 c
-243.2 d
0.0 a
-263.8 b
-99.1 c
-251.9 d
0.0 a
-98.5 c
   
B3LYPultrafine         0.0 a
-251.6 b
-98.4 c
-245.1 d
  0.0 a
-242.7 d
          0.0 a
-99.9 c
0.0 a
-99.0 c
-252.8 d
  0.0 a
-100.6 c
0.0 a
-263.9 b
-99.1 c
-252.0 d
     
B3PW91 0.0 a
-209.1 b
-101.0 c
0.0 a
-301.0 b
-131.3 c
-290.0 d
0.0 a
-301.0 b
-131.3 c
-290.0 d
0.0 a
-293.7 b
-130.2 c
-285.6 d
0.0 a
-207.4 b
-69.4 c
-201.4 d
0.0 a
-203.9 b
-66.9 c
-197.3 d
0.0 a
-206.4 b
-68.0 c
-197.6 d
0.0 a
-221.7 b
-75.4 c
-212.5 d
0.0 a
-216.2 b
-70.4 c
-205.3 d
0.0 a
-206.8 b
-64.5 c
-200.0 d
  0.0 a
-72.7 c
0.0 a
-205.4 b
-70.9 c
-196.6 d
0.0 a
-216.3 b
-69.3 c
-205.9 d
  0.0 a
-207.7 b
-198.3 d
0.0 a
-215.7 b
 
NC
NC
 
mPW1PW91 0.0 a
-202.8 b
-172.9 d
0.0 a
-291.5 b
-278.3 d
0.0 a
-295.2 b
-282.0 d
0.0 a
-288.8 b
-278.5 d
0.0 a
-196.9 b
-188.5 d
0.0 a
-193.3 b
-184.3 d
0.0 a
-196.2 b
-184.9 d
0.0 a
-211.0 b
-199.6 d
0.0 a
-209.1 b
-195.9 d
0.0 a
-199.7 b
-190.5 d
    0.0 a
-195.0 b
-183.9 d
0.0 a
-205.8 b
-193.1 d
  0.0 a
-201.1 b
-189.4 d
   
NC
NC
 
M06-2X 0.0 a
-75.8 c
0.0 a
-119.2 c
0.0 a
-295.7 b
-119.3 c
-268.5 d
0.0 a
-114.6 c
0.0 a
-186.9 b
-41.9 c
-164.8 d
0.0 a
-38.9 c
0.0 a
-39.8 c
0.0 a
-48.7 c
0.0 a
-42.8 c
0.0 a
-184.9 b
-34.6 c
  0.0 a
-45.9 c
0.0 a
-43.5 c
0.0 a
-195.2 b
-41.5 c
  0.0 a
-43.8 c
0.0 a
-195.1 b
-41.7 c
     
PBEPBE 0.0 a
-203.3 b
-102.5 c
-189.8 d
0.0 a
-289.0 b
-128.8 c
-286.4 d
0.0 a
-289.0 b
-128.8 c
-286.4 d
0.0 a
-282.4 b
-125.2 c
-283.0 d
0.0 a
-199.9 b
-66.6 c
-203.2 d
0.0 a
-196.6 b
-64.2 c
-199.0 d
0.0 a
-199.4 b
-64.9 c
-199.1 d
0.0 a
-214.1 b
-72.1 c
-213.9 d
0.0 a
-208.7 b
-67.4 c
-206.7 d
0.0 a
-198.6 b
-61.3 c
-200.7 d
  0.0 a
-69.3 c
0.0 a
-197.4 b
-67.3 c
-197.2 d
0.0 a
-209.0 b
-66.2 c
-207.2 d
  0.0 a
-199.7 b
-67.7 c
-199.2 d
0.0 a
-208.1 b
-66.0 c
-205.9 d
 
NC
NC
 
PBEPBEultrafine         0.0 a
-199.9 b
-66.6 c
-203.2 d
              0.0 a
-67.2 c
0.0 a
-66.2 c
  0.0 a
-67.6 c
0.0 a
-66.0 c
     
PBE1PBE 0.0 a
-90.2 c
0.0 a
-121.8 c
0.0 a
-121.8 c
0.0 a
-122.0 c
0.0 a
-190.3 b
-58.4 c
-182.0 d
0.0 a
-58.4 c
0.0 a
-57.0 c
0.0 a
-64.4 c
0.0 a
-59.3 c
0.0 a
-53.2 c
  0.0 a
-61.8 c
0.0 a
-59.8 c
0.0 a
-58.2 c
  0.0 a
-60.9 c
0.0 a
-58.3 c
     
HSEh1PBE 0.0 a
-91.1 c
0.0 a
-291.2 b
-122.6 c
-279.1 d
0.0 a
-122.6 c
0.0 a
-122.8 c
0.0 a
-193.6 b
-58.6 c
-186.1 d
0.0 a
-56.0 c
0.0 a
-192.9 b
-182.6 d
0.0 a
-64.7 c
0.0 a
-59.6 c
0.0 a
-53.2 c
  0.0 a
-62.0 c
0.0 a
-60.0 c
0.0 a
-202.2 b
-58.3 c
-190.4 d
  0.0 a
-61.1 c
0.0 a
-58.3 c
     
TPSSh         0.0 a
-203.0 b
-67.1 c
-198.9 d
  0.0 a
-201.9 b
-65.5 c
-194.9 d
    0.0 a
-203.0 b
-62.9 c
-198.3 d
      0.0 a
-212.4 b
-67.4 c
-204.2 d
           
wB97X-D     0.0 a
-309.5 b
-139.2 c
-286.5 d
  0.0 a
-221.3 b
-86.7 c
-203.2 d
  0.0 a
-221.6 b
-85.9 c
-200.7 d
  0.0 a
-231.5 b
-88.3 c
-208.4 d
    0.0 a
-236.3 b
-89.3 c
-213.8 d
0.0 a
-225.1 b
-89.4 c
-204.3 d
0.0 a
-231.5 b
-87.1 c
-208.9 d
    0.0 a
-231.3 b
-87.3 c
-208.4 d
     
B97D3   0.0 a
-334.5 b
-156.6 c
-328.6 d
    0.0 a
-236.3 b
-84.3 c
-235.7 d
  0.0 a
-235.6 b
-82.8 c
-231.6 d
  0.0 a
-244.3 b
-84.9 c
-238.9 d
  0.0 a
-240.2 b
-79.2 c
-235.0 d
0.0 a
-252.5 b
-88.8 c
-247.2 d
  0.0 a
-244.8 b
-82.5 c
-239.9 d
    0.0 a
-244.0 b
-82.3 c
-238.8 d
     
STO-3G 3-21G 3-21G* 6-31G 6-31G* 6-31G** 6-31+G** 6-311G* 6-311G** 6-31G(2df,p) 6-311+G(3df,2p) TZVP cc-pVDZ cc-pVTZ cc-pVQZ aug-cc-pVDZ aug-cc-pVTZ aug-cc-pVQZ cc-pV(T+d)Z daug-cc-pVTZ
Moller Plesset perturbation MP2 0.0 a
-356.1 b
-178.0 c
-243.2 d
0.0 a
-422.1 b
-202.2 c
-361.4 d
0.0 a
-422.1 b
-202.2 c
-361.4 d
0.0 a
-207.6 c
-354.8 d
0.0 a
-255.6 b
-98.7 c
-205.7 d
0.0 a
-252.4 b
-98.3 c
-203.8 d
0.0 a
-98.8 c
0.0 a
-255.7 b
-98.3 c
-206.0 d
0.0 a
-251.2 b
-95.9 c
-201.8 d
0.0 a
-230.8 b
-76.0 c
-186.1 d
  0.0 a
-215.8 d
0.0 a
-249.7 b
-100.2 c
-202.2 d
0.0 a
-238.6 b
-83.1 c
-192.4 d
0.0 a
-80.6 c
0.0 a
-245.7 b
-94.7 c
-198.3 d
0.0 a
-236.1 b
-81.9 c
0.0 a
-80.7 c

NC
NC
 
MP2=FULL 0.0 a
-177.4 c
0.0 a
-421.3 b
-201.3 c
-360.6 d
0.0 a
-421.3 b
-201.3 c
-360.6 d
0.0 a
-416.6 b
-206.7 c
-354.1 d
0.0 a
-253.1 b
-95.7 c
-204.0 d
0.0 a
-249.9 b
-95.2 c
-202.0 d
0.0 a
-251.6 b
-95.8 c
-202.7 d
0.0 a
-252.3 b
-94.9 c
-203.1 d
0.0 a
-247.3 b
-92.0 c
-198.3 d
0.0 a
-219.2 b
-64.7 c
    0.0 a
-247.9 b
-97.7 c
-200.9 d
0.0 a
-230.4 b
-74.2 c
-186.0 d
0.0 a
-75.1 c
0.0 a
-90.7 c
0.0 a
-227.4 b
-71.8 c
0.0 a
-74.1 c

NC
NC
 
MP3         0.0 a
-253.7 b
-110.5 c
-217.1 d
                             
MP3=FULL         0.0 a
-251.6 b
-107.7 c
-215.6 d
  0.0 a
-253.0 b
-109.7 c
-216.3 d
                         
MP4   0.0 a
-212.4 c
-371.3 d
    0.0 a
-121.5 c
-233.8 d
      0.0 a
-119.0 c
      0.0 a
-123.6 c
0.0 a
-107.2 c
  0.0 a
-117.5 c
       
MP4=FULL   0.0 a
-211.6 c
    0.0 a
-118.7 c
              0.0 a
-121.4 c
0.0 a
-98.4 c
  0.0 a
-112.8 c
       
B2PLYP         0.0 a
-260.2 b
-236.6 d
        0.0 a
-252.4 b
      0.0 a
-262.7 b
-237.3 d
    0.0 a
-261.6 b
     
Configuration interaction CID   0.0 a
-188.0 c
0.0 a
-394.0 b
-188.0 c
-349.6 d
0.0 a
-388.2 b
-194.7 c
-346.0 d
0.0 a
-252.5 b
-99.1 c
-211.8 d
    0.0 a
-258.2 b
-101.7 c
-216.5 d
                       
CISD   0.0 a
-189.1 c
0.0 a
-395.2 b
-189.1 c
-351.5 d
0.0 a
-389.8 b
-195.7 c
-348.2 d
0.0 a
-254.8 b
-100.8 c
-214.5 d
    0.0 a
-260.2 b
-103.4 c
-218.8 d
                       
STO-3G 3-21G 3-21G* 6-31G 6-31G* 6-31G** 6-31+G** 6-311G* 6-311G** 6-31G(2df,p) 6-311+G(3df,2p) TZVP cc-pVDZ cc-pVTZ cc-pVQZ aug-cc-pVDZ aug-cc-pVTZ aug-cc-pVQZ cc-pV(T+d)Z daug-cc-pVTZ
Quadratic configuration interaction QCISD   0.0 a
-411.4 b
-216.5 c
-371.5 d
0.0 a
-411.4 b
-216.5 c
-371.5 d
0.0 a
-407.1 b
-223.1 c
-369.1 d
0.0 a
-267.5 b
-122.0 c
-230.9 d
0.0 a
-265.0 b
-122.1 c
-229.3 d
0.0 a
-122.4 c
0.0 a
-269.4 b
-122.0 c
-231.7 d
0.0 a
-120.0 c
0.0 a
-248.8 b
-103.3 c
    0.0 a
-263.6 b
-125.0 c
-228.6 d
0.0 a
-256.9 b
-109.3 c
  0.0 a
-119.8 c

NC
NC
     
QCISD(T)         0.0 a
-131.0 c
              0.0 a
-133.2 c
0.0 a
-115.6 c
  0.0 a
-126.3 c
0.0 a
-113.5 c
     
Coupled Cluster CCD   0.0 a
-408.2 b
-213.0 c
-365.9 d
0.0 a
-408.2 b
-213.0 c
-365.9 d
0.0 a
-402.6 b
-219.2 c
0.0 a
-260.9 b
-116.5 c
-222.4 d
0.0 a
-258.3 b
-116.6 c
-220.8 d
0.0 a
-116.8 c
0.0 a
-263.3 b
-116.5 c
-223.8 d
0.0 a
-114.6 c
      0.0 a
-257.7 b
-119.6 c
-221.4 d
0.0 a
-103.8 c
  0.0 a
-115.0 c
       
CCSD         0.0 a
-265.4 b
-120.8 c
        0.0 a
-247.2 b
    0.0 a
-124.1 c
0.0 a
-255.3 b
-108.3 c
  0.0 a
-119.1 c
0.0 a
-106.5 c
     
CCSD=FULL         0.0 a
-263.2 b
-117.9 c
        0.0 a
-235.4 b
    0.0 a
-121.8 c
0.0 a
-247.4 b
-99.3 c
  0.0 a
-115.4 c
       
CCSD(T)         0.0 a
-270.1 b
-130.7 c
-237.8 d
              0.0 a
-132.9 c
    0.0 a
-126.3 c
       
CCSD(T)=FULL         0.0 a
-127.9 c
              0.0 a
-130.8 c
0.0 a
-106.4 c
  0.0 a
-122.6 c
0.0 a
-103.4 c
     
STO-3G 3-21G 3-21G* 6-31G 6-31G* 6-31G** 6-31+G** 6-311G* 6-311G** 6-31G(2df,p) 6-311+G(3df,2p) TZVP cc-pVDZ cc-pVTZ cc-pVQZ aug-cc-pVDZ aug-cc-pVTZ aug-cc-pVQZ cc-pV(T+d)Z daug-cc-pVTZ

Methods with effective core potentials (select basis sets)
CEP-31G CEP-31G* CEP-121G CEP-121G* LANL2DZ SDD cc-pVTZ-PP aug-cc-pVTZ-PP Def2TZVPP
hartree fock HF 0.0 a
-345.4 b
-184.9 c
-292.4 d
0.0 a
-235.6 b
-106.7 c
-184.0 d
0.0 a
-384.8 b
-190.2 c
-336.3 d
0.0 a
-290.7 b
-119.7 c
-242.1 d
0.0 a
-397.2 b
-195.3 c
-351.0 d
0.0 a
-397.6 b
-195.1 c
-351.1 d
    0.0 a
-292.5 b
-111.8 c
-247.4 d
density functional B1B95
-64986.0 b
-64964.6 d

-65065.5 b
-65046.7 d
             
B3LYP 0.0 a
-292.3 b
-158.5 c
-270.5 d
0.0 a
-212.4 b
-97.6 c
-193.6 d
0.0 a
-327.9 b
-167.9 c
-312.2 d
0.0 a
-257.0 b
-109.3 c
-244.0 d
0.0 a
-330.6 b
-165.3 c
-316.8 d
0.0 a
-330.5 b
-165.1 c
-316.6 d
    0.0 a
-262.5 b
-98.1 c
-251.2 d
PBEPBE                 0.0 a
-206.8 b
-64.8 c
-205.3 d
Moller Plesset perturbation MP2 0.0 a
-359.7 b
-193.5 c
-291.2 d
0.0 a
-204.8 b
-86.4 c
-146.4 d
0.0 a
-398.9 b
-333.6 d
0.0 a
-247.9 b
-103.5 c
-194.2 d
0.0 a
-410.6 b
-210.4 c
-348.8 d
0.0 a
-411.3 b
-210.8 c
-349.4 d
    0.0 a
-236.1 b
-81.4 c
-190.4 d

Single point energy calculations (select basis sets)
6-311+G(3df,2p) cc-pVDZ cc-pVTZ aug-cc-pVDZ aug-cc-pVTZ cc-pV(T+d)Z
Moller Plesset perturbation MP2FC// HF/6-31G*
NC
NC
 
NC
NC
   
NC
NC
MP2FC// B3LYP/6-31G*
NC
NC

NC
NC

NC
NC
   
NC
NC
MP2FC// MP2FC/6-31G*
NC
NC
 
NC
NC

NC
NC

NC
NC

NC
NC
MP4// HF/6-31G*
NC
NC
 
NC
NC
   
NC
NC
MP4// B3LYP/6-31G*  
NC
NC

NC
NC
   
NC
NC
MP4// MP2/6-31G*
NC
NC
 
NC
NC
   
NC
NC
Coupled Cluster CCSD// HF/6-31G*    
NC
NC
   
NC
NC
CCSD(T)// HF/6-31G*    
NC
NC
   
NC
NC
CCSD// B3LYP/6-31G*
NC
NC
         
CCSD(T)// B3LYP/6-31G*
NC
NC
         
CCSD(T)//B3LYP/6-31G(2df,p)    
NC
NC
   
NC
NC
CCSD// MP2FC/6-31G*
NC
NC
   
NC
NC

NC
NC
 
CCSD(T)// MP2FC/6-31G*
NC
NC
   
NC
NC

NC
NC
 
NC = not calculated
For descriptions of the methods (AM1, HF, MP2, ...) and basis sets (3-21G, 3-21G*, 6-31G, ...) see the glossary in section I.C. Predefined means the basis set used is determined by the method.
gaw refers to the group additivity method implemeted in the NIST Chemistry Webbook.
See section Calculated; Vibrations; Scale Factors; Scale factors to list vibrational scaling factors.
See section Calculated; Vibrations; Scale Factors; Calculate a scale factor to calculate a vibrational scaling factor for a given set of molecules.