THERMOCHEMISTRY OF SUBSTITUTED BENZENES - EXPERIMENTAL STANDARD MOLARENTHALPIES OF FORMATION OF O-TERPHENYL, M-TERPHENYL, AND P-TERPHENYLSAND 1,3,5-TRIPHENYLBENZENE

The standard (p(0) = 0.1 MPa) molar enthalpies of formation Delta(f)H( m)(0)(cr) at the temperature T = 298.15 K were measured by using combu stion calorimetry for o-, p-, and m-terphenyl and 1,3,5-triphenylbenze ne. The standard molar enthalpies of vaporization Delta(1)(g)H(m)(0) o r sublimation Delta(cr)(g)H(m)(0) of the compounds were obtained from the temperature variation of the vapor pressure measured in a now syst em. Molar enthalpies of fusion Delta(cr)(1)H(m)(0) of the compounds we re measured by d.s.c. Values of the stabilized interactions of phenyl substituents were derived from the enthalpies of formation in the gas phase of the terphenyls. [GRAPHICS] (C) 1997 Academic Press Limited.