Modified calculations of hydrocarbon thermodynamic properties

✍ Scribed by Min Hsien Liu; Cheng Chen

• Publisher: John Wiley and Sons
• Year: 2006
• Tongue: English
• Weight: 92 KB
• Volume: 27
• Category: Article
• ISSN: 0192-8651
• DOI: 10.1002/jcc.20353

✦ Synopsis

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 (Δ__H__~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 Δ__H__~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. © 2006 Wiley Periodicals, Inc. J Comput Chem 27: 537–544, 2006