A methodology has been developed for the semi-automatic assignment and checking of formal oxidation states for metal atoms in the majority of metallo-organic complexes stored in the Cambridge Structural Database (CSD). The method uses both chemical connectivity and bond-length data, via ligand donor group templates and bond-valence sums, respectively. In order to use bond-length data, the CSD program QUEST has been modified to allow the coordination sphere of metal atoms to be recalculated using user-defined criteria at search time. The new methodology has been used successfully to validate the +1, +2 and +3 oxidation states in 743 four-coordinate copper complexes in the CSD for which atomic coordinates are available in ca 99% of structures using one or other method, and both succeed for >86% of structures.

The assignment and validation of metal oxidation states in the Cambridge Structural Database

Molecular architecture of copper(I) thiometallate complexes. Example of a cubane with an extra face, (NPr4)3[MS4Cu4Cl5] MMo, W)

Sm2+ in BAM: fluorescent probe for the number of luminescing sites of Eu2+ in BAM

Publisher Summary This chapter focuses on the progress in the field of interaction between optical centers and their surroundings (the ligands) over the past decade. The chapter presents the models necessary for the discussion and the phenomena to be expected. These models are mainly the configurational coordinate model and the Forster–Dexter model of energy transfer. The phenomena involved are radiative and nonradiative transitions, spectral band shapes, including zero-phonon lines, as well as energy transfer and energy migration. The various developments are illustrated by several examples. The existence of optical centers in solids, in liquids, and in molecules is well known and their properties have been studied intensively. Two of these are well established, which are; (1) the phenomenon of optical absorption, leading to colored compositions and (2) the phenomenon of emission of radiation (luminescence). The chapter presents the configurational coordinate diagram that describes the interaction of an optical center with its surroundings in the absence of center-center interaction. The chapter also discusses the interaction between two centers that results in energy transfer. If luminescent centers come closer together, they may show interaction with each other that result in new phenomena.

Interaction Between Optical Centers and their Surroundings: An Inorganic Chemist'S Approach

The characteristic IR spectra of heterothiometallic cluster compounds

Heteronuclear W(Mo)CuS complexes of dialkyldithiocarbamate. Syntheses of (Et4N)2[MCu3S4(dtcR2)3] and structures of (Et4N)2[MCu3S4(dtcC5H10)3]· DMF (M = W or Mo)

A novel tungsten-copper-sulfur cluster with dialkyldithiocarbamate: preparation and structure of (Et4N)2 [W2Cu5S8(S2CNMe2)3]

The first triangular V3S72+ complex. Synthesis and structure of (Et4N) [V3S7(Me2dtc)3] · CH3CN

Syntheses and crystal structures of copper(I) complexes with alkyl-thioallophanate derivatives

A trinuclear linear Mo-Fe-Mo dialkyldithiocarbamate complex [Et4N] {[Me2dtcMoO(μ-S)2]2Fe} has been obtained and structurally characterized, which contains two Me2dtcMoO(μ-S)2 units coordinated to a central tetrahedral Fe atom. A comparison of the structural parameters indicates the metal oxidation states of 2Mo(v) + Fe(III). The 1H NMR shows chemical shifts of Me2dtc ligands at δ 10.14 and δ 9.40 with the intensity ratio of 1:1. Tbe cyclic voltammogram displays a reversible couple at -1.41 V/ -1.36 V responsible for 1-/2-anions of tbe complex and an irreversible oxidation at 0.5 V, which seems to show the apparent lack of stability for its neutral species (Me2dtcMoOS2)2Fe.

Liu Qiutian

Papers

Heteronuclear W(Mo)CuS complexes of dialkyldithiocarbamate. Syntheses of (Et4N)2[MCu3S4(dtcR2)3] and structures of (Et4N)2[MCu3S4(dtcC5H10)3]· DMF (M = W or Mo)

A novel tungsten-copper-sulfur cluster with dialkyldithiocarbamate: preparation and structure of (Et4N)2 [W2Cu5S8(S2CNMe2)3]

The first triangular V3S72+ complex. Synthesis and structure of (Et4N) [V3S7(Me2dtc)3] · CH3CN

Syntheses and crystal structures of copper(I) complexes with alkyl-thioallophanate derivatives

A trinuclear Mo‐Fe‐Mo cluster compound [Et4N] {[Me2dtcMoO(μ‐S)2]2Fe} containing dialkyldithiocarbamate ligand