ΔHf: -61.7 kcal/mol, REF: NIST Chemistry WebBook, NIST Standard Reference Database, No. 69; W. G. Mallard, P. J. Linstrom, Eds., National Institute of Standards and Technology, Gaithersberg, http://webbook.nist.gov/chemistry. I.P.: 10.1 eV, REF: R. D. Levin, S. G. Lias, "Ionization Potentials and Appearance Potential Measurements," 1971-1981, Natl. Stand. Ref. Data Ser., Natl. Bur. Stand. 71, (1982), Cat. No. C13.48:71.