Possible stable structures of various 2,2'-bipyridine (bpy) and 1,10-phenanthroline (phen) complexes, [Ni(bpy)(3)](2+), [Co(bpy)(3)](2+), [Fe(bpy)(3)](2+) and Fe(phen)(2)(NCS)(2), were optimized for different spin states of the metals, and the spectra computed for every form were compared with the experimental IR spectra of the compounds. It is demonstrated that the changes in spin states of the metals influence both geometry and vibrational spectra of the complexes. Spectral changes are predicted not only in the low frequency range, corresponding to metal-ligand vibrations, but also in the mid-IR range, where ligand vibrations are active. Detailed computational analysis in combination with the corresponding spectroscopic experiment shows that the spectral changes are of a similar character for complexes with the same ligands independent on the central metal and can be used as spectroscopic markers of the electronic state of the latter. Found spectral markers have been validated at a number of complexes of Fe(II), Ni(II), Co(II), Zn(II) and Cu(II) with bpy and phen ligands.

A novel type of cyclic P,N-ligands, pyridyl containing phospholanes, has been synthesized in a moderate yield by the reaction of primary phosphines with 1,4-dichlorobutane in a superbasic medium. A series of homo tetranuclear octahedral Cu4I4L2, dinuclear tetrahedral Cu2I2L3, and dinuclear "head-to-tail" Cu2I2L2 luminescent complexes with these ligands were obtained. All the compounds were characterized using a range of spectroscopic and computational techniques, and in the case of some Cu4I4L2 and Cu2I2L3 complexes, by single crystal X-ray diffraction. The structural diversity of the obtained complexes was reflected in their photophysical properties: phosphorescence spectra of the compounds display emission in broad spectral range of 471-615 nm. TD-DFT computations allow the assignment of a single emission band around 550 nm for Cu2I2L3 complexes and 471 nm for Cu2I2L2 complex to a vertical triplet-singlet transition from a metal-to-ligand and halide-to-ligand charge-transfer (3)(M + X)LCT excited state, whereas a second band at around 600 nm in the spectra of octahedral Cu4I4L2 complexes was assigned predominantly to Cu4I4 cluster-centered ((3)CC) excited state.

The unique L 2 Cu 6 I 6 complexes containing two Cu 3 I 3 units have been obtained via reaction of 1,5-diaza-3,7-diphosphacyclooctanes bearing ethylpyridyl substituents at phosphorus atoms with an excess of copper iodide. The structure of one of the complexes was confirmed by X-ray diffraction. It was shown that the complexes can exist in two crystalline phases with different parameters of the unit cell, which were detected by the PXRD data analyses. The solvent-free crystalline phases of the complexes display rare solid-state white emission at room temperature, which is observed due to the presence of two broad bands in the emission spectra with maxima at 464 and 610 nm. Quantum chemical computations show that the high-energy band has 3 (M+X)LCT origin, whereas the low-energy band is interpreted as 3 CC. The quantum yields of white luminescence of complexes reach 15−20%.

An efficient approach for an accurate quantum mechanical (QM) modeling of infrared (IR) spectra of condensed-phase systems is described. An ensemble of energetically low-lying cluster structures of a solute molecule surrounded by an explicit shell of solvent molecules is efficiently generated at the semiempirical tight-binding QM level and then reoptimized at the density functional theory level of theory. The IR spectrum of the solvated molecule is obtained as a thermodynamic average of harmonically computed QM spectra for all significantly populated cluster structures. The accuracy of such simulations in comparison to experimental data for some organic compounds and their solutions is shown to be the same or even better than the corresponding QM computations of the gas-phase IR spectrum for the isolated molecule.

A new carbon paste electrode is described, which contains the room temperature ionic liquid (RTIL) tri(tertbutyl)(dodecyl)phosphonium tetrafluoroborate as binder. The advantages of this electrode are a high conductivity, very wide electrochemical window (5.6 V from 2.7 to −2.9 V, one of the widest ever reported for RTILs), stability in time, and reproducibility. This RTIL-carbon paste electrode (CPE) allows determining the current-voltage characteristics of redoxactive compounds. Thus, the newly synthesized insoluble compound poly-tris(μ 2 -1,1′-ferrocenediylphenylhydrophosphinato-phenylphosphinato)-iron(III) tetrahydrofuran solvate {μ 2 -[Fe II (η 5 -C 5 H 4 -P(PhOO)(η 5 -C 5 H 4 -P(PhOOH))] 3 Fe III }·THF was studied, and a quasi-reversible three-electron oxidation could be observed at a potential more positive than that of ferrocene. A comparison of voltammograms on the paraffin-CPE and on the novel RTIL-CPE shows the advantages of the latter.