New lanthanide–nitrogen bond-valence parameters

Abstract

The bond-valence parameters (R(ij)), which connect bond valences and bond lengths, have been computed for lanthanide-nitrogen bonds. It has been found that values of bond-valence parameters decrease with increasing lanthanide atomic number in coordination compounds, and that they are smaller than the R(ij) parameters of inorganic compounds. As expected, the lanthanide-nitrogen bond-valence parameters are larger than lanthanide-oxygen bond-valence parameters. There are no obvious dependencies between the number of N atoms in the coordination sphere and the bond-valence parameter value.

Nitrogen‐Rich Compounds of the Lanthanoids: Highlights and Summary

“…In compounds 3 and 4, these parameters are 2.38 and 2.46 , respectively. The R(LnÀN) values are, therefore, higher than the average values of N-ligands [47]. The valencebond parameters R(LnÀO) of La(1) and La(2) in 2 are both 2.15 , and thus slightly higher than the average as well [48].…”

“…1 has to be modified as shown in Eqn. 2 [47]. In this modification, the contribution of the LnÀO bonds to the total valence of Ln is subtracted from the formal valence of V(Ln) ¼ 3.…”

Magnesium sulphate complexes with hexamethylenetetramine and 1,10-phenanthroline

“…The sulphate(VI) anion in both compounds can be considered as fully delocalised (Table 2), however, in both cases one S-O bond is slightly but clearly shorter and one longer than two others S-O bonds. The bond valences were computed as , 29], where R ij is the bond-valence parameter (in the formal sense R ij can be considered as a parameter equal to the idealised single-bond length between i and j atoms for given b [30,31]) and b was taken as 0.37 Å [32,33]. The R Mg-O and R Mg-N were taken as 1.693 and 1.85, respectively [33].…”

Alkali metal halogenides coordination compounds with hexamethylenetetramine

“…The symmetry generated atoms indicated by dashed lines are obtained by symmetry transformations (C2A, C3A, H2AA, H2BA, H3AA, H3BA, IA1: x, -y, z; N2A: -x, y, -z; K1A: -x, -y, -z; K1B, O1A: -x, -y, -z ? 1) the formal sense R ij can be considered as a parameter equal to the idealised single-bond length between i and j atoms for given b) and b was taken as 0.37 Å [47][48][49][50]. The R Li-O , R Na-O , R Na-N , R K-N , R K-O , R K-I , R Rb-N , R Rb-O , and R Rb-I were taken as 1.466, 1.80, 1.93, 2.26, 2.13, 2.28, 2.37, 2.26 and 3.01, respectively [51].…”