Synthesis, characterization, structures, and DFT study of zinc(II) complexes with tributylphosphine chalcogenides

The authors are grateful to the Tunisian Ministry of High Education and Scientific Research for financial support (LR99ES14) of this research.Four new zinc(II) complexes of the type [ZnCl2(n-Bu3PE)2] (E = O ( 1 ), S ( 2 ), Se ( 3 ) or Te ( 4 )) have been synthesized from zinc(II) chloride and the ligands n-Bu3PE giving yields of 56-88%. The adducts were characterized by multinuclear (31P, 13C and 77Se) NMR, conductivity, IR spectroscopy and by X-ray analyses. The zinc complexes 1 – 4 are comprised of two ligands coordinated to the metal centre in a distorted tetrahedral arrangement. The P=E bond lengths of 1.497(7) (E = O), 2.000(4) (E = S) and 2.178(2) Å (E = Se) in these complexes are slightly elongated compared to those in the free ligand. In addition, a DFT/B3LYP theoretical study on the geometry optimization of the title ligands and their zinc complexes has been carried out in order to support and complement the experimental data and to further investigate the nature of the chalcogenide-metal interaction. The results show good agreement between the experimental and theoretical data.PostprintPeer reviewe

Étude théorique des propriétés physico-chimiques et spectroscopiques de Cu

L'étude théorique ab initio de Cu2S, CuS, CU2O et CuO nous a permis de calculer leurs paramètres géométriques et de montrer que ces molécules sont fortement polarisées. Nous avons aussi déterminé les nombres d'onde des modes normaux de vibration de Cu2S et CuS. L'étude théorique du spectre électronique de Cu2S montre que toutes les transitions permises amènent à des raies dans le domaine ultraviolet. La détermination des premiers et seconds potentiels d'ionisation, adiabatiques et verticaux des molécules Cu2X, ainsi que de la géométrie des ions moléculaires Cu2X+ et CU2X2+ nous a permis de bien préciser le diagramme des orbitales moléculaires de Cu2S et Cu2O

Mechanistic study of bismuth-catalyzed direct benzylation of 2,4-pentanediones: the case of BiCl3 and generalization

International audienc

Paleobiodiversity and tectono-sedimentary records in the Mediterranean tethys and related eastern areas : proceedings of the 1st Springer Conference of the Arabian Journal of Geosciences (CAJG-1), Tunisia 2018

Conference of the Arabian Journal of Geosciences (CAJG-1), Hammamet, TUN, 12-/11/2018 - 15/11/2018This edited volume contains the best papers accepted for presentation during the 1st Springer Conference of the Arabian Journal of Geosciences (CAJG-1), Tunisia 2018.The volume shares the latest results from paleontological, biostratigraphic and sedimentological studies by experienced researchers mainly from research institutes in the Mediterranean and Middle East.Main topics include: paleontology, biostratigraphy, sedimentology, paleoclimatology and geomorphology. Some new insights are given on paleobiodiversity and major biological tools for biostratigraphy, patterns, mechanisms and processes of meso-cenozoic sedimentation in the Mediterranean and Middle East. In particular, case studies are included to highlight the major controlling factors of Tethyan biosphere-geosphere interactions as inferred from the Mediterranean and Middle East regions. The book is of interest to all researchers in the fields of different disciplines involved in the sedimentary geolog

Measurements of line intensities for some lines of methyl iodide in the ν<SUB>5</SUB> and ν<SUB>3</SUB> + ν<SUB>6</SUB> bands

International audienceThe line intensities for RR- and PP- sub-branch transitions in the ν5 and ν3 + v6 bands of CH3I are measured for the first time for 270 lines with 5 ≤ J ≤ 40 and 4 ≤ K ≤ 11 using a multi-pressure fitting method with a Voigt profile. Seven spectra have been recorded using the Bruker IFS125HR Fourier Transform Spectrometer at the AILES beamline of SOLEIL Synchrotron with a resolution of 0.002 cm-1 for pressures between 0.270 and 2.433 mbar. Line intensities are analyzed and discussed as a function of the rotational quantum numbers. On average, the accuracy of the measured data is estimated to be about 4.5% for the two bands. The measured line intensities have been used to derive the vibrational transition moment, the Herman-Wallis parameters as well as the intensities of the two bands. The values for the band strengths of the ν5 and ν3 + v6are respectively 46.47 ± 2.63 cm-2 atm-1 and 14.79 ± 1.60 cm-2 atm-1. The measured line intensities were reproduced with mean values of difference of about 8.3% and 3.8% for the ν5 and ν3 + v6 bands respectively. At pressure used in this work, analysis of the overlapped line using the Rosenkranz profile demonstrates a negligible line-mixing effect on line intensities

Insights on the interaction of Zn 2+ cation with triazoles: Structures, bonding, electronic excitation and applications

International audienc

Premier inventaire des communautés de diatomées périphytiques des tributaires du lac Ichkeul, Tunisie

International audienceAn initial inventory of diatom biodiversity at 12 sites draining into Lake Ichkeul, northern Tunisia, was performed in summer 2014, together with the characterisation of metal pollution status by analysing trace metal concentrations to determine Water Quality Indices. The maximum values of Fe, Mn, Sb, Zn, Cu and Pb were all below the national and international standard, except for Fe in Hammam Ben Abbes thermal spring and Sb in Wadi Tinja, indicating that the surface water of the Ichkeul basin was largely acceptable. Diatom community composition and specific descriptors, including quantification of morphological alterations and mortality, were used to diagnose environmental stress. High abundances of Achnanthidium minutissimum (Kützing) Czarnecki were observed at the Fe-rich site, which could reflect a response to metal contamination. Diatoms were stressed mostly by the influence of temperature and salinity, which drove species composition and increased mortality. Further research is required on the ecology of diatoms in Ichkeul thermal springs. The use of diatoms as indicators of ecosystem health in the Ichkeul area requires additional knowledge of diatom diversity in the ecoregion

Paleobiodiversity and tectono-sedimentary records in the Mediterranean tethys and related eastern areas : proceedings of the 1st Springer Conference of the Arabian Journal of Geosciences (CAJG-1), Tunisia 2018

Conference of the Arabian Journal of Geosciences (CAJG-1), Hammamet, TUN, 12-/11/2018 - 15/11/2018This edited volume contains the best papers accepted for presentation during the 1st Springer Conference of the Arabian Journal of Geosciences (CAJG-1), Tunisia 2018.The volume shares the latest results from paleontological, biostratigraphic and sedimentological studies by experienced researchers mainly from research institutes in the Mediterranean and Middle East.Main topics include: paleontology, biostratigraphy, sedimentology, paleoclimatology and geomorphology. Some new insights are given on paleobiodiversity and major biological tools for biostratigraphy, patterns, mechanisms and processes of meso-cenozoic sedimentation in the Mediterranean and Middle East. In particular, case studies are included to highlight the major controlling factors of Tethyan biosphere-geosphere interactions as inferred from the Mediterranean and Middle East regions. The book is of interest to all researchers in the fields of different disciplines involved in the sedimentary geolog

Paleobiodiversity and tectono-sedimentary records in the Mediterranean tethys and related eastern areas : proceedings of the 1st Springer Conference of the Arabian Journal of Geosciences (CAJG-1), Tunisia 2018

Conference of the Arabian Journal of Geosciences (CAJG-1), Hammamet, TUN, 12-/11/2018 - 15/11/2018This edited volume contains the best papers accepted for presentation during the 1st Springer Conference of the Arabian Journal of Geosciences (CAJG-1), Tunisia 2018.The volume shares the latest results from paleontological, biostratigraphic and sedimentological studies by experienced researchers mainly from research institutes in the Mediterranean and Middle East.Main topics include: paleontology, biostratigraphy, sedimentology, paleoclimatology and geomorphology. Some new insights are given on paleobiodiversity and major biological tools for biostratigraphy, patterns, mechanisms and processes of meso-cenozoic sedimentation in the Mediterranean and Middle East. In particular, case studies are included to highlight the major controlling factors of Tethyan biosphere-geosphere interactions as inferred from the Mediterranean and Middle East regions. The book is of interest to all researchers in the fields of different disciplines involved in the sedimentary geolog