the data on HC18OOH, HCO^OH, H^COOH, HCOOD, DCOOH and DCOOD, together with ... rs(C—0) = 1.352(3) Ä, r s (0-H) = 0.956(5) A,
The Structure of the Other Rotamer of Formic Acid, eis-HCOOH12 E. Bjarnov and W. H. Hocking* Physikalisch-Chemisches Institut, Justus-Liebig-Universität, Gießen
and Max-PIanek-Institut für Radioastronomie, Bonn, B.R.D. Z. Naturforsch. 33a, 6 1 0 - 6 1 8 (1978); received February 26, 1978 The very weak microwave spectra of six isotopically substituted species of formic acid in the eis rotamer form (i.e. with the two hydrogen atoms eis to each other) have been studied. From the data on HC 18 OOH, HCO^OH, H^COOH, HCOOD, DCOOH and DCOOD, together with the previously published data for HCOOH, the complete substitution structure of the eis rotamer of formic acid has been derived. The structure is: r s (C—H) = 1.105(4) A, r s ( C = 0 ) = 1.195(3) A, r s (C—0) = 1.352(3) Ä, r s ( 0 - H ) = 0.956(5) A,
