Search results for "physical chemistry"

Properties and Reactivity of Hydroxides of Group 13 Elements In, Tl, and Nh from Molecular and Periodic DFT Calculations

2019

Adsorption energies, Eads, of gaseous hydroxides of In, Tl, and the superheavy element Nh on surfaces of Teflon and gold are predicted using molecular and periodic relativistic DFT calculations. Th...

Über gemischte bindungen in der IV. Hauptgruppe

1984

Abstract The reaction of Ph 3 PbLi with Ph 3 SnCl or Ph 3 GeCl gives Ph 3 PbSnPh 3 and Ph 2 PbGePh 3 , respectively; there is no reaction with Ph 3 SiCl. Ph 3 SiLi reacts with Ph 3 PbCl to form a regular 1 : 1 Pb 2 Ph 6 · Si 2 Ph 6 phase. The compounds have been investigated by mass, NMR and vibrational spectra: 207 Pb NMR chemical shifts with respect to PbMe 2 −79.8 (Pb 2 Ph 6 ), −256.5 (Ph 3 PbSnPh 3 ), −271.5 ppm (Ph 3 PbGePh 3 ); stretching vibrations 112 (PbPb), 125 (PbSn), 138 cm −1 (PbGe). The crystal structures have been determined and refined to R = 0.061 (Ph 3 PbSnPh 3 , −40°C), 0.053 (Ph 3 PbGePh 3 , −50°C), 0.068 (Pb 2 Ph 6 · Si 2 Ph 6 , 20°C); bond lengths 285 (PbPb),…

Molecular Multi‐Wavelength Optical Anion Sensors

2010

Polychromatic fingerprinting of simple anions (halides, oxo anions) is achieved by employing neutral and charged multicolor fluorescent probes based on ferrocene-spaced dansyl and naphthyl groups (1/1 + ; 2/2 + ). The conformation of the neutral double dye sensor 2 has been elucidated by NMR spectroscopic techniques (in solution), by X-ray crystallography (solid state) and by DFT calculations (gas phase). The double-dye receptors 2/2 + exhibit specific emission responses in the presence of anions X- when excited at the absorption maxima of the dyes (fingerprint).

A systematic study of the optical properties of mononuclear hybrid organo-inorganic lanthanoid complexes

2020

A series of hybrid organo-inorganic mononuclear lanthanoid complexes, [n-NBu4]3[LnH(PW11O39)(phen)2]·H2O, denoted as LM4-1-Ln (Ln = DyIII, TbIII, EuIII, NdIII, ErIII, HoIII and GdIII), were synthesized via hydrothermal synthesis and were structurally characterized by X-ray diffraction. The optical properties of all complexes have been investigated in the solid state. The temperature-dependent emission spectra of LM4-1-Dy, LM4-1-Tb and LM4-1-Eu complexes show intense lanthanoid emissions in the visible region, while LM4-1-Nd shows near-infrared (NIR) luminescence. The EuIII complex shows typical strong red emissions from the 5D0 → 7F0,1,2,3,4 transitions, with the CIE colour coordinates (0.6…

Molecular structure and electric properties of N -methyl- N -nitroaniline and its derivatives

2001

A comparative study of the molecular structure of N-methyl-N-nitroaniline and its derivatives is carried out employing the Kerr effect and dipole moments methods in combination with the crystallographic analysis. The obtained experimental structural data agree with the quantum-chemical calculations by the B3LYP/6-31G p and MP2/3-21G p methods. The measurement and calculation results are used to draw conclusions about the mutual interaction and role of various substituents to the Nmethyl-N-nitroaniline molecule. q 2001 Elsevier Science B.V. All rights reserved.

Complexes of organometallic compounds. LI. The correlation between 119Sn Mössbauer isomer shifts and partial atomic charges on tin in R3SnL compounds

1985

Abstract The 119Sn Mossbauer isomer shift parameters, δ, of compounds R3SnL (R = AlK, Ph; L = F, Cl, OH, OR′, CN, NCS, NCO, N3) have been correlated to partial atomic charges on tin QSn, calculated according to a valence state electronegativity equalization procedure carried out by the CHELEQ program. A unique δ/QSn correlation has been obtained for all the five-coordinated R3SnL species by using average δ parameters for the AlK3IV derivatives.

Copper(II) Complexes with Derivatives of Barbiturate

1984

Abstract NaCuL2(OH).1,5H2O, KCuP2(OH).1H2O, Na2CuL4 and K2CuP4-8H2O (HL=Phenobarbitone and HP=Methyl Phenobarbitone) were prepared and characterized by elemental analysis, IR and electronic spectral data and magnetic susceptibility measurements. The ESR spectra show and octahedral environment for the Cu(II) ion.

Stoichiometric Control of the Magnetic Properties in Copper( II ) Cyano‐Bridged Bimetallic Complexes

2003

Control of the Cu2+ ion coordination environment affords a 1D, magnetically diluted compound, [Cu(cis-chxn)2]3[Fe(CN)6]2·7H2O (1) and the 2D ferromagnetic material [Cu(cis-chxn)]3[Fe(CN)6]2·6H2O (2) with a critical temperature, Tc, of 3.5 K. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)

Magnetic Properties of a New Hexahalorhenate(IV) Compound and Structural Comparison with Its Hexahaloplatinate(IV) Analog

2020

Solution Chemistry of Element 106:  Theoretical Predictions of Hydrolysis of Group 6 Cations Mo, W, and Sg

2001

Fully relativistic molecular density-functional calculations of the electronic structure of hydrated and hydrolyzed complexes have been performed for the group 6 elements Mo, W, and element 106, Sg. By use of the electronic density distribution data, relative values of the free energy changes and constants of hydrolysis reactions were defined. The results show hydrolysis of the cationic species with the formation of neutral molecules to decrease in the order Mo > W > Sg, which is in agreement with experiments for Mo, W, and Sg. For the further hydrolysis process with the formation of anionic species, the trend is reversed:  Mo > Sg > W. A decisive energetic factor in the hydrolysis process …