Electronic absorption spectra for copper(II) polyamine complexes

Abstract

The preparations and visible and ultraviolet absorption spectra are reported for a series of copper(11) complexes with linear and cyclic aliphatic ligands which each have four nitrogen donor atoms. Data are compared with that for 16 analogous complexes. For linear polyamines of different chain length the ligand field strength, as denoted by vmax (visible), is found to increase with increasing thermodynamic stability of the copper(11) complex in aqueous solution. For linear and cyclic ligands the ligand field strength is a maximum for complexes containing a combination of five- and six-membered chelate rings.

Inter-String Arrays of Bimetallic Assemblies with Alternative Cu2+−Cl−Cu2+and Cu−NC−M (M = Co3+, Fe+3, Cr+3) Bridges: Syntheses, Crystal Structure, and Magnetic Properties

“…The intense bands at ∼240 and ∼ 270 nm are commonly seen for 1 − 3 . The band near 240 nm seems to correspond to the L σ → Cu charge transfer, and the band at 270 nm to a band near 260 nm found for K 3 [M(CN) 6 ] (259 nm for M = Co and Fe, 261 nm for M = Cr).…”

A Chloro-Bridged Dinuclear Copper(II) Cationic Complex of a 15-Membered Tetraaza Macrocyclic Ligand

“…Preparations of the copper(H) and nickel(II) compounds of the 15-membered tetraaza macrocycle 6,8,8,13,13,15hexamethyl-1,5, 9,12-tetraazacyclopentadeca-5,15 ( 1 )diene (cis- [15]diene) have been reported previously (Hedwig, Love & Powell, 1970;Love & Powell, 1968). The salt diene)] (CIO4)2 has also been described.…”

“…~-Chloro-l,l,l-trichloro-2-(12-methyl-12-nitro-l,4,7,10tetraazacyclotridecane)dicopper(II) has one copper(H) ion, Cul, with square-planar coordination involving the 13-membered macrocycle, with one chlorine of a (Cu2C14) e-anion interacting axially in a square-pyramidal° arrangement [Cul--CI 2.266 (2) diene)](ClO4h was prepared by reaction of 4,4,9,9-tetramethyl-5,8-diazadodecane-2,11 -dione diperchlorate (Curtis, 1982) with propane-l,3-diamine and reaction of the resulting solution with basic copper(II) carbonate (Hedwig, Love & Powell, 1970). 1 Partial occupancy (see below).…”

Investigation of Molecular Interaction of Amino Acids in Aqueous N-Propanol Solutions at 308.15 K

“…The liquids and liquid mixtures help chemical physicist to explore the "dynamic behavior" of rigid molecules, using both physical and chemical methods. Denaturation of globular proteins in aqueous solutions is a fundamental biological process which till date is not completely understood and continues to be a subject of extensive investigations [1]. Knowledge of various solute-solute and solute-solvent interactions is very important to understand various fundamental phenomena like stability of proteins, folding/unfolding processes, denaturation of proteins etc., in aqueous solutions [2].…”