POTASSIUM μ-(TRANS-HYPONITRITO-N,N′-BIS(PENTACYANOCOBALTATE(III)) AND POTASSIUM μ-(TRANS-HYPONITRITO-O,O′)-BIS(PENTACYANOCOBALTATE(III))

K6[Co2(CN)10(N2O2)]·2H2O (orange salt) was prepared by reaction of [Co(NO)(NH3)5]Cl2 with an aqueous solution of potassium cyanide. K6[Co2(CN)10(N2O2)]·4H2O (yellow salt) was obtained by adding an aqueous solution of the orange salt to methanol. On the basis of IR and Raman spectra for their 14NO- and 15NO-salts, and of IR spectra for their gaseous decomposition products, the orange salt is considered to be a linkage isomer of the yellow salt with respect to the trans-hyponitrito bridge. It is presumed that the orange salt is potassium μ-(trans-hyponitrito-N,N′-bis{pentacyanocobaltate(III)}, the yellow salt being potassium μ-(trans-hyponitrito-O,O′)-bis{pentacyanocobaltate(III)}.