title: Modified calculations of hydrocarbon thermodynamic properties.
abstract: A test set of 65 hydrocarbons was examined to elucidate theoretically their thermodynamic properties by performing the density-functional theory (DFT) and ab initio calculations. All the calculated data were modified using a three-parameter calibration equation and the least-squares approach, to determine accurately enthalpies of formation (DeltaH(f)), entropies (S), and heat capacities (C(p)). Calculation results demonstrated that the atomization energies of all compounds exhibited an average absolute relative error ranging between 0.11- 0.13%, and an DeltaH(f) of formation with a mean absolute absolute error (M.|A.E.|) ranging from only 5.7-6.8 kJ/mol (1.3-1.6 kcal/mol) (i.e., those results correlated with those of Dr. Herndon's 1.1 kcal/mol). Additionally, the entropy ranged from 3.5-4.2 J/mol K (0.8-1.0 cal/mol K) M.|A.E.|; a heat capacity between 2.3-2.9 J/mol K (0.5-0.7 cal/mol K) M.|A.E.| was obtained as well.
authors.affiliation: Department of Applied Chemistry, Chung Cheng Institute of Technology, National Defense University, Ta-Hsi, Taoyuan, 33509 Taiwan, Republic of China. mcliu@ccit.edu.tw
authors.forename: Min Hsien
authors.initials: MH
authors.lastname: Liu
authors.forename: Cheng
authors.initials: C
authors.lastname: Chen
mesh_terms: D006838:Hydrocarbons / Q000737:chemistry*; D008432:Mathematical Computing; D008956:Models, Chemical; D011789:Quantum Theory; D013816:Thermodynamics
chemical_list: D006838:Hydrocarbons