Semiempirical molecular orbital estimation of the relative stability of bianthryls produced by anthracene pyrolysis

Journal Article · Sun Aug 01 00:00:00 EDT 1993 · Combustion and Flame; (United States)

DOI:https://doi.org/10.1016/0010-2180(93)90070-J· OSTI ID:6372576

Mulholland, J A; Mukherjee, J; Wornat, M J; Sarofim, A F; Rutledge, G C ^[1]

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1. Massachusetts Inst. of Tech., Cambridge, MA (United States). Dept. of Chemical Engineering

The pyrolysis of pure anthracene at temperatures between 1,200 and 1,500 K produced all six bianthryl isomers whose relative yields appear to be related to steric factors. To evaluate the hypothesis that thermodynamic factors govern the product distribution of bianthryls in this system, the relative enthalpies and entropies of biaryl isomers were estimated by molecular orbital modeling, using the semiempirical AM1 (Austin Model 1). Computational analysis of several isomer sets demonstrates that the relative stabilities of a large number of biaryl isomers are determined largely by steric interactions caused by structural features defined as bays, coves, and fjords. These steric factors affect both the degree of biaryl twist in the preferred conformation and the freedom of internal rotation. Molecular orbital modeling supports the hypothesis that a thermodynamic distribution of bianthryl isomers is produced by anthracene pyrolysis.

• OSTI ID: 6372576
• Journal Information: Combustion and Flame; (United States), Vol. 94:3; ISSN 0010-2180
• Country of Publication: United States
• Language: English

Related Subjects

02 PETROLEUM
ANTHRACENE
PYROLYSIS
CHEMICAL REACTION KINETICS
CHEMICAL REACTION YIELD
ENTHALPY
ENTROPY
ISOMERS
MOLECULAR ORBITAL METHOD
STABILITY
STEREOCHEMISTRY
THERMODYNAMICS
AROMATICS
CALCULATION METHODS
CHEMICAL REACTIONS
CONDENSED AROMATICS
DECOMPOSITION
HYDROCARBONS
KINETICS
ORGANIC COMPOUNDS
PHYSICAL PROPERTIES
REACTION KINETICS
THERMOCHEMICAL PROCESSES
THERMODYNAMIC PROPERTIES
YIELDS
020400* - Petroleum- Processing