The microwave spectra of five isotopic species of formic acid have been investigated, and values of the rotational constants B and C have been obtained. For HC12OOH, B=12 055.1 Mc, C=10 416.0 Mc; for HC12OOD, B=11 762.5 Mc, C=9970.1 Mc; for DC12OOH, B=12 055.6 Mc, C=9955.8 Mc; for DC12OOD, B=11 759.9 Mc, C=9534.1 Mc; and for HC13OOH, B=12 053.7 Mc, C=10 378.9 Mc. The following structural parameters have been fitted to these rotational constants: rC–H=1.085 A, rC=O=1.245 A, rC–O=1.312 A, rO–H=0.95 A, ∠OCO=124°18′, ∠COH=107°48′. The C=O bond has been estimated to have 75% double-bond character. The torsional frequency was found to be 667±41 cm—1 and a barrier height of roughly 17 kcal/mole is indicated.
No takes yet. Share an insight, caveat, or question.
Lerner et al. (1957) studied this question.