55 research outputs found
(Z)-4-(2-Naphthylamino)pent-3-en-2-one
No full textThe title compound, C15H15NO, which was synthesized under solvent-free conditions by the reaction of acetoacetone and 2-naphthylamine, adopts a Z conformation about the C=C bond. The enamine–ketone fragment is approximately planar [maximum deviation = 0.026 (3) Å] and forms a dihedral angle of 39.78 (3)° with the naphthalene ring system. An intramolecular N—H...O hydrogen bond is observed
(Adipato-κ2O,O′)diaqua[bis(pyridin-2-yl-κN)amine]cobalt(II) trihydrate
No full textIn the monomeric title complex, [Co(C6H8O4)(C10H9N3)(H2O)2]·3H2O, the distorted octahedral CoN2O4 coordination environment comprises two N-atom donors from the bidentate dipyridyldiamine ligand, two O-atom donors from one of the carboxylate groups of the bidentate chelating adipate ligand and two water molecules. In addition, there are three solvent water molecules which are involved in both intra- and inter-unit O—H...O hydrogen-bonding interactions, which together with an amine–water N—H...O hydrogen bond produce a three-dimensional framework
Spectroscopic studies of the Eu3+ and Er3+ ions in the fluorozirconate LaZr2F11 matrix
No full textAn investigation by optical spectroscopy of the Eu3 + and Er3 + active ions in the crystallized fluorozirconate matrix LaZr2F11 is presented. The D-5(1) --> F-7(0-5) emission lines of Eu3 + are used to extract the F-7(0-5) energy scheme and the observed extinctions permit the deduction of irreducible representations (IRREPS) associated with corresponding sub-levels in the D-2 symmetry. The crystal field analysis was carried out on a 387 x 387 basis set, comprising the F-7, D-5(1,2,3) F-5(1,2), (5)G(1,2,3) and P-3(1,2,3,4,5,6) terms of the Eu-3 (+) 4f(6) configuration. The deviation and rms are 6.8 and 7.9 cm (-1), respectively for 38 levels and ten parameters. The experimental crystal field parameters are in good agreement with the ab-initio ones. Moreover, the relative intensities of the D-5(0) --> F-7(2,3,4) emissions are well reproduced by an 'ab-initio' calculation, except for three lines. The Er3 + ions introduced in LaZr2F11, microcrystals also lie in an unique crystallographic site. A total of 31 energy levels were recorded and the crystal field analysis led to 6.6 and 7.8 cm (-1) for the deviation and rms, respectively, for nine variable parameters taken into account. The experimental CF parameters for Er3 + and Eu3 + are very similar, which seems to show that the host lattice contracts around the smaller Er3 + ion. The informations given by both Eu3 + and Eu3 + optical probes in LaZr2F11 are very consistent with the structure previously determined for the isotypic PrZr2F11 fluoride. (C) 2000 Elsevier B.V. B.V. All rights reserved.CNRS, CEMES, F-31055 Toulouse 4, FranceUNESP, Inst Quim, BR-14800900 Araraquara, SP, BrazilUniv Blaise Pascal, CNRS, Upres A 6002, Lab Mat Inorgan, F-63177 Aubiere, FranceEcole Cent Paris, Lab SPMS, UMR 8580, F-92295 Chatenay Malabry, FranceUNESP, Inst Quim, BR-14800900 Araraquara, SP, Brazi
ChemInform Abstract: The Crystal Structure of Tl3ThF7: A Case of Stereochemical Activity of Tl+ Lone Pair in Fluorides.
No full text
- …
