Gordon C. Percy

Infrared spectrum of isotopically substituted cis-bis(glycino)copper (II) monohydrate

Abstract The i.r. spectra of cis -bis(glycino)copper (II) monohydrate cis -[Cu(gly) 2 (H 2 O)], and its 15 N -, 18 O - and 1- 13 C -isotopically labelled analogues have been measured. The effects of isotopic substitutions indicate the need for revision of certain ligand assignments and allow assignments of the copper—ligand vibrations.

The infrared spectra (3500-140 cm−1) of the 2,2'-bipyridine, 2-aminomethylpyridine and ethylenediamine adducts and the sodium tris-compounds of cobalt(II), nickel(II) and zinc(II) acetylacetonates

SummaryThe M(acac)2B and NaM(acac)3 complexes (M = Coll, Nill orZnll; acac=acetylacetonateanion; B=2,2′=bipyridine, 2-aminomethylpyridine or ethylenediamine) have been prepared and their i.r. spectra determined over the 3500-140 cm−1 range. Complete band assignments have been made on a comparative basis, with the effects of ligand substitution and metal ion substitution being considered. Bands in the i.r. spectra of the complexes which are associated with 2,2′-bipyridine, 2-aminomethylpyridine and ethylenediamine arc in excellent agreement with values previously established for these ligand and metal-ligand vibrations, in related complexes. Band assignments for acetylacetonate anion and metal-acetylacetonate vibrations substantiate those made in certain of the previously published papers. The method of assignment adopted has allowed the complete assignment of bands in the i.r. spectra of the metal complexes.

Infrared and electronic spectra of N-salicylideneglycinate complexes of cobalt and nickel

Abstract The i.r. spectra of six 18 O -Iabelled and six 15 N -labelled complexes of the type M ( R -sal-gly)(H 2 O) n ( M = Co(II) and Ni(II), R -sal-gly = various 3- and 5-substituted N -salicylideneglycinates) derived from labelled glycine, and their unlabelled analogues are discussed. Assignments of characteristic ligand and metal-ligand vibrations are based on the effects of the isotopic substitution. Evidence from electronic spectral and magnetic moment data indicates that these complexes possess octahedral stereochemistries. Two new mixed valency compounds of formulae [Co(H 2 O) 6 ][Co( R -sal-gly) 2 ] 2 ·2H 2 O ( R = H and 3-NO 2 ) have been isolated and characterised. Band assignments in their electronic spectra are proposed.

Examination of the ratio. nu. /sup D//. nu. /sup H/ for infrared bands assigned to the C--H(D) and ring vibrations in metal complexes of quinoline, pyridine, aniline, and their fully-deuterated analogues

The infrared spectra of sixteen metal complexes comprising the ligands quinoline, pyridine, aniline and their fully-deuterated analogues have been examined in order to determine the ratio D v/H v f...

Band assignments in the i.r. spectrum of cis,cis-bis(glycinato)cis-bis(imidazole)nickel(II) by multiple isotopic labelling

Abstract The i.r. spectra of cis -[Ni(gly) 2 (Him) 2 ] (gly = glycinate ion, Him = imidazole) and its isotopically-labelled analogues have been determined over the range 4000-150 cm −1 . 18 O -, 15 N -, 1- 13 C -, 2- 13 C -, and 2,2- d 2 -labelling of the coordinated glycinate yields assignments for the internal glycinate modes and the nickel—oxygen and nickel—nitrogen stretching and bending vibrations while deuteration of imidazole (Him- d 3 ) provides assignments for the internal modes of the coordinated imidazole rings and for the nickel—imidazole vibrations. The results, combined with those of previous multiple isotopic labelling studies on glycinate complexes, enable some general conclusions to be reached on the i.r. spectra of these compounds.

Structural information on some metal(II) complexes of glycylglycine from their infrared spectra

Abstract The infrared spectra of thirteen metal(II) complexes of glycylglycine have been determined and are discussed in relation to their known or probable structures. A distinction between various structures is possible on the basis of differences in the spectral band patterns of these complexes.

Infrared spectra of oxovanadium (IV) complexes of isotopically labelled N-salicylideneamino acids

Abstract The i.r. spectra of 15N-, 18O- and 13C-labelled [VO(sal-AA)(H2O)] complexes (Sal-AA = N-salicylideneamino acid anion) derived from 15N-, 18O- and 1-13C-glycine, 15N- and 18O-L-alanine and 15N-L-leucine, and their unlabelled analogues, L-phenylalanine, L-valine, L-isoleucine and L-methionine are discussed. Assignments of characteristic ligand and metal—ligand vibrations are based on the effects of the isotopic substitutions.

Infrared Spectra of Barbiturate Complexes

Abstract The assignment and shifts of the carbonyl stretching frequencies in the infrared spectra of the complexes of general formula [M(barb)2L2] (M = Ni, Cu, Zn; barb = 5,5-disubstituted-barbiturate, L = pyridine (py), β-picoline (β-pic), imidazol (imid))are discussed in relation to their known crystal structures.

The infrared spectra (600-140 cm−1 of the imidazole, pyrazine and pyrimidine adducts of cobalt(II), nickel(II) and zinc(II) acetylacetonates

SummaryThe complexes M(acac)2(imidazole)2 (M = Co or NO and [M(acac)2B]n (M = Co, Ni or Zn; B = pyrazine or pyrimidine) have been prepared and their i.r. spectra determined over the 600–140 cm−1. range. The metal-oxygen and metal-nitrogen stretching frequencies, (M-O) and v(M-N), are assigned on the basis of the band shifts induced by deuteriation of the adducted base and by substitution of the metal ion. Three or fourv(M-O) bands are observed within the 600-200 cm−1 range. The twov(M-O) bands of higher frequency are considered to the coupled with internal ligand modes. TwovM-N) bands are observed within the 280–170 cm−1. range. The metal-ligand stretching frequencies are in good agreement with the values previously established for these vibrations in the [M(imidazole)6]2+ and Ni(acac)2(pyridine)2 complexes.

Assignments of the metal-ligand stretching vibrations in the infrared spectra of some metal (II) complexes of substituted salicylaldehydes

Abstract The i.r. spectra of 50 complexes of general formula [M(R-Sal)2B2] (M = Co(II), Ni(II), Zn(II); B = H2O or pyridine (py); R-Sal = variously 3- and 5-substituted salicylaldehydes) have been determined in the range 710–150 cm−1. On the basis of their spectral band patterns, all these complexes are assigned trans-octahedral structures. Assignments of metal—oxygen and metal—nitrogen stretching frequencies are made by observing the effects of metal ion substitution, replacement of the adducted base, and deuteration of the pyridine ring on the i.r. spectra.