Alkali metal halogenides coordination compounds with hexamethylenetetramine

Abstract

, have been synthesized and characterised by IR spectroscopy, thermogravimetry coupled with differential thermal analysis, elemental analysis and X-ray crystallography. Both the sodium compounds are isostructural in a solid state, an isostructurality is also observed between compounds containing potassium and rubidium iodides. The sodium compounds exist as dimers (dinuclear core of the complex ion is created by two sodium cations and two water molecules). The molecules of potassium and rubidium compounds are assembled to the two dimensional hybrid nets. The each potentially multifunctional ligand (the hmta) exists in the outer coordination sphere in lithium compounds, acts in a monodentate mode in sodium compounds and in bidentate-bridging modes in potassium and rubidium compounds. The lithium ions are four coordinated, and the sodium, potassium and rubidium ions are six coordinated. Thermal analyses show that the investigated compounds decompose gradually with the formation of alkali metal halides which, during the further heating, are totally removed or they undergo partial decomposition to oxides.

Structurally diverse coordination compounds of zinc as effective precursors of zinc oxide nanoparticles with various morphologies

“…These shifts originate from involvement of hmta molecules in O—H•••N hydrogen bonds, which are stronger than C—H•••N hydrogen bonds existing in pure hmta . The formation of one or two coordination bonds by hmta in 2 – 5 leads to differentiation of energy of CN and CH oscillators, which reflects in multiplication of the majority of hmta bands (to doublet, triplet or even quartet) in the spectra of these compounds . The splitting of bands assigned to vibrations of CC and CH bonds of carboxylate anions results from a different structural environment of each carboxylate anion in a particular compound and consequently involving them in different intermolecular interactions.…”

On the Coordination Behaviour of the hmta Toward Alkali Metal Cations in Presence of Perchlorate Anions

“…The lithium forms the 1:2 (M:L) compound (1) and the sodium forms the 1:1 (M:L) compound (2), nevertheless of the metal to ligand molar ratio used in syntheses. This is in contrast to the composition of the bromide salts, in which the M:L ratio was always 1:1 [5].…”

“…This situation is analogues to the reactions between alkali metals bromides and hmta, in which only two coordination compounds of whole series were created (i. ) and other alkali metals bromides crystallised separately from the hmta [5]. The lithium forms the 1:2 (M:L) compound (1) and the sodium forms the 1:1 (M:L) compound (2), nevertheless of the metal to ligand molar ratio used in syntheses.…”

“…The study of alkali metal ions bonding in coordination systems has been recently an active area of research [1][2][3][4][5][6] due to both, the important applications of such compounds (e.g. in medicine [7] and material chemistry [8]) and significance of alkali metal ions in biological systems.…”

“…The present study deals with the possibility of differencing the both structures and properties of subsequent alkali metals salts via an N-donor ligand and it is a continuation of investigations of the s block metal ion coordination compounds with the commercially used compound, hexamethylenetetramine (hmta, Scheme 1) [5,6,26,27]. Besides the practical applications (e.g.…”