Vibrational spectra of nitrogen-15-substituted hexa-amminenickel(II) chloride, hexa-amminecobalt(III) chloride, and tetra-amminezinc(II) iodide

I.r. spectra of [Ni(15NH3)6]Cl2 and [Co(15NH3)6]Cl3 and Raman and i.r. spectra of [Zn(15NH3)4]I2 are reported and compared with the spectra of the normal ammines. The 14N–15N isotope shifts can be used to solve some assignment problems. Reliable skeletal force constants have been calculated by use of the nitrogen isotope shifts as additional data.