On the Reactivity and Stability of Iodide–Nitride–Sulfide Clusters of Neodymium and Dysprosium

The thermal decomposition of cluster Nd₃I₅(S₂)(S₂N₂)(THF)10 (I) at 50–400°C affords a mixture of products among which tetrahydrofuran (THF), sulfur, diiodine, HI, H₂S, CS₂, S₃N₆, S₃N₅, MeI, thiophene, tetrahydrothiophene, diiodobutane, iodobutene, and NdI₃ are identified. The treatment of Ln₃I₅(S₂)(S₂N₂)(THF)₁₀ (Ln = Nd (I), Dy (II)) with phenanthroline (Phen) in THF at room temperature results in the partial substitution of ТНF to form new complexes Ln₃I₅(S₂)(S₂N₂)(THF)₄(Phen)₃. The dissolution of compound I in pyridine gives a pyridine (Py) complex Ln₃I₅(S₂)(S₂N₂)(THF)3(Py)₇. The dissolution of compounds I and II in acetonitrile at 20°C is accompanied by the fast rearrangement and fragmentation of the complexes to form LnI₃(MeCN)₆, [LnI(S₂)(MeCN)], and [LnI(S₂N₂)(MeCN)]. Complex I in THF does not react with white phosphorus, carbon monoxide, fullerene C₆₀, and chromium hexacarbonyl.     

Tin(IV) complexes based on 2-hydroxy-3,6-di-tert-butyl-para-benzoquinone: Syntheses,structures, and electrochemical behavior in solution

A series of new tin(IV) complexes based on 2-hydroxy-3,6-di-tert-butyl-para-benzoquinone (LH) of the general formula L₂SnR₂ (R = Me (I), Et (II), Bu ⁿ (III), Ph (IV)) and LSnMe₃ (V) were synthesized. The obtained compounds were characterized by IR and ¹H, ¹³C and ¹¹⁹Sn NMR spectroscopy and elemental analysis. The X-ray diffraction analysis was carried out for complexes L₂Sn(Bu ⁿ )₂ (III) and LSnMe₃ (V). The low-frequency region of the IR spectra, which has not earlier been studied in detail, was interpreted for compounds I–V and previously described complex LSnPh₃ (VI). The electrochemical properties of LH and related tin complexes I–VI were studied. The nature of the hydrocarbon groups at the metal atom affects the stability of the intermediates formed in the electrochemical reactions.     

Infrared spectroscopic studies of transition metal complexes and polarizability effect

The literature data on substituent influence on the CS, CN, NC, NN, and NO stretching frequencies (ν) in the IR spectra and in specific cases on their respective stretching force constants (k) have been analyzed for 28 series of the transition metal complexes. The ν and k values were first established to depend not only on the inductive and resonance effects but on the polarizability of substituents as well. The contribution of the polarizability effect varies from 0 to 57% with the type of series.     

Carbon 1s binding energy and substituent effects in C-centered radical cations

The carbon 1s binding energies (E _b) measured by X-ray photoelectron spectroscopy or obtained from quantum chemical calculations for 18 series of compounds in which the reaction center is the C atom are analyzed. It was established for the first time that E _b values in carboncentered radical cations depend on the inductive, resonance, and polarizability effects of substituents.     

PRESSURE-VELOCITY EQUILIBRIUM HYDRODYNAMIC MODELS

This article describes mathematical models for phase separated mixtures of materials that are in pressure and velocity equilibrium but not necessarily temperature equilibrium. General conditions for constitutive models for such mixtures that exhibit a single mixture sound speed are discussed and specific examples are described.     

Bond dissociation energies in organometallic systems: substituent effects

A knowledge of the factors determining the magnitude of the bond dissociation enthalpy (BDE) is of importance to the advancement of theoretical organometallic chemistry and from the practical standpoint. The central atom and the substituents bound to it influence the BDE values; however, the interplay between the BDE and the substituent effects remains unknown. In this work, the literature data on substituent influence on the BDE of lithium, sodium, copper, silver, mercury, aluminium, gallium, silicon, germanium, tin, lead, phosphorus, antimonium, chromium, iron, cobalt, nickel, rhodium, and iridium compounds (37 series) have been analyzed, using the correlation analysis. Generally, the BDE values were first established to depend on the joint influence of the inductive, resonance, polarizability, and steric effects of substituents. The contribution of the polarizability effect ranges up to about 40%. Copyright © 2014 John Wiley & Sons, Ltd.     

Polarity of para-disubstituted benzene derivatives: a correlation analysis of the substituent effect

Russian Chemical Bulletin - The article is concerned with the influence of resonance donor substituents RD on the dipole moments μ of molecules 1,4-RDC6H4RA containing resonance acceptor...     

Ion-Dipole Interaction (Polarization Effect) in Compounds of the Group 14 Elements (A Review)

Russian Journal of General Chemistry - The review summarizes the data on the dependence of the properties of compounds of the silicon subgroup elements on the reactive site and substituents. When...     

Polarizability effect in transition metal carbonyl complexes

The literature date on substituent influence on the carbonyl stretching frequencies (ν), CO stretching force constants (k), as well as ¹³C NMR carbonyl chemical shifts (δ) have been analyzed for 19 series of the transition metal carbonyl complexes. It was established for the first time that the ν, k and δ values depend not only on the inductive and resonance effects but also on the polarizability of substituents. The polarizability contribution ranges up to 37%.     

Transition metal NMR chemical shifts and polarizability effect in organometallic complexes

The literature data on substituent influence on the ⁵¹V, ⁵⁵Mn, ⁵⁷Fe, ⁵⁹Co, ⁶¹Ni, ⁹⁵Mo, ¹⁰³Rh, ¹⁸³W, ¹⁸⁷Os and ¹⁹⁵Pt NMR chemical shifts (δ) and on J (M, P; M = Mn, Fe, Mo, Rh, W, Os) coupling constants have been analyzed for 30 series of the organometallic complexes. It has been established for the first time that the δ and J values depend on the inductive, resonance and polarizability effects of substituents. The polarizability effect is caused by the partial charge on the central M atom. The contribution of this effect ranges from 3 to 86%. Copyright © 2009 John Wiley & Sons, Ltd.