Infrared band assignments for L-alanine and the nickel(II) and copper(II) complexes of L- and β-alanine

Abstract

The i.r. spectra of L-alanine, its ¹⁸O- and ¹⁵N-labelled analogues, hydrated and anhydrous [Ni(L-AlaO)₂], anhydrous trans-[Cu(L-AlaO)₂](L-AlaO =L-alaninate anion), their ¹⁸O- and ¹⁵N-labelled analogues, trans-[Ni(β-AlaO)₂-(OH₂)₂], and [Cu(β-AlaO)₂](β-AlaO =β-alaninate anion) have been recorded in the 150–4 000 cm^–1 region. The effects of the isotopic substitutions indicate the need for revision of certain band assignments in the spectra of L-Ala and its complexes. Band assignments in the spectra of the β-AlaO complexes have been accomplished by comparison with the spectrum of trans-[Ni(GlyO)₂(OH₂)](GlyO = glycinate anion).