Group Contributions to ΔHf
°(g) and S°(g) at 298 K*
| Group | ΔHf° (kJ/mol) | S° (J/mol K) |
|---|---|---|
| Cd-(F)2 | -324.3 | 156.1 |
| Cd-(Cl)2 | -7.5 | 176.1 |
| Cd-(F)(H) | -157.3 | 137.2 |
| Cd-(Cl)(H) | 8.8 | 148.1 |
| Cd-(Br)(H) | 53.1 | 160.2 |
| Cd-(I)(H) | 102.5 | 169.5 |
| CB-(F) | -179.1 | 67.4 |
| CB-(Cl) | -15.9 | 79.1 |
| CB-(Br) | 44.8 | 90.4 |
| CB-(I) | 100.4 | 99.2 |
| C-(CB)(F)3 | -680.7 | 179.1 |
| C-(CB)(Br)(H)2 | -28.9 | 0.0 |
| C-(CB)(I)(H)2 | 35.1 | 0.0 |
| C-(F)3(C) | -662.7 | 177.8 |
| C-(F)2(H)(C) | -457.3 | 163.6 |
| C-(F)(H)2(C) | -216.7 | 148.1 |
| Group | ΔHf° (kJ/mol) | S° (J/mol K) |
|---|---|---|
| C-(F)2(C)2 | -405.8 | 74.5 |
| C-(F)(H)(C)2 | -202.5 | 58.6 |
| C-(F)(C)3 | -183.7 | 0.0 |
| C-(F)2(Cl)(C) | -444.8 | 169.5 |
| C-(Cl)3(C) | -86.6 | 210.9 |
| C-(Cl)2(H)(C) | -79.1 | 182.8 |
| C-(Cl)(H)2(C) | -65.3 | 158.2 |
| C-(Cl)2(C)2 | -81.6 | 0.0 |
| C-(Cl)(H)(C)2 | -53.6 | 73.6 |
| C-(Cl)(C)3 | -53.6 | -22.6 |
| C-(Br)(H)2(C) | -22.6 | 170.7 |
| C-(Br)(H)(C )2 | -14.2 | 0.0 |
| C-(Br)(C)3 | -1.7 | -8.4 |
| C-(I)(H)2(C) | 33.5 | 177.8 |
| C-(I)(H)(C )2 | 44.8 | 92.9 |
| C-(I)(C)3 | 54.4 | 0.0 |
| C-(Cl)(C)(O)(H) | -93.3 | 64.4 |
*The subscripts "d" and "t" designate carbon atoms in carbon-carbon double and triple bonds; "a", an allenic carbon; "B", an aromatic carbon; "A", a nitrogen atom in a nitrogen-nitrogen double bond; and "I", a nitrogen atom in a nitrogen-carbon double bond. Bracketed values are estimated.
Reference: S.W. Benson, F.R. Cruickshank, D.M. Golden, G.R. Haugen, H.E. O'Neal, A.S. Rodgers, R. Shaw, and R. Walsh, Chem. Rev., 69, 279 (1969).