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Crystal structure and spectroscopic properties of mercury(II) halide complexes. Part 4. Crystal and molecular structure and circular dichroism spectra of the chiral 1:1 adduct (S)s(S)c(-)589-methyl 2-phenylbutyl thioethermercury(II) chloride
No full textSynthesis and Characterization of Chiral Thioethers and Mercury (II) Halide Complexes. Part 3. Conformational Energy Calculation and NMR and CD Spectra of the Chiral Isothiochroman (R)-(-)-4-Ethyl-3,4-dihydro-1H-2-benzothiine.
No full textThe effect of pressure on CD spectra of chiral octahedral transition metal-ligand complexes: L-, D- and (LD)(Cr[(+)(S,S)mebdtp]3)
No full textThe effect of pressure on circular dichroism spectra of a chiral helicoidal chromium complex
No full textThe effect of pressure on circular dichroism (CD) spectra of the octahedral chiral Λ- and Δ-tris-[cyclic O,O′,1(R), 2(R)-dimethylethylene dithiophosphato]chromium(III) complexes, Λ- and Δ-Cr[(R,R)bdtp]3, in the solid state has been studied. The pressure range investigated was 0-4 GPa. A method for measuring CD spectra under pressure is described. Results on polycrystalline samples in nujol indicate that the configuration at the metal centre of the chiral chromium complex inverts from the Δ- to the Λ-form, which eventually is the most stable at high pressure
Induced CD on the d-d transitions of square planar MS4 chromophoric groups of Ni(II) complexes with enantiomeric dithiophosphate ligands: (+)589(-)(CD662)Ni[(R,R)bdtp]2, and (-)589 (+)(CD662)Ni[(S,S)bdtp]2
No full textNew bis-chelate square-planar complexes of Ni(II) with enantiomeric ligands, cyclo-O,O'-(R,R)- or -(S,S)-1,2-dimethylethylene dithiophosphate ion, have been synthesized and characterized via UV-vis and CD spectroscopy and an X-ray crystal structure investigation, the results of which have been correlated. The absence of an intrinsic configurational chirality on the metal has allowed to obtain CD spectra due only to the less intense chirality induced on the Ni(II) electronic d-d transitions by the ligands outer ring conformations and absolute configuration of the 2 and 3 carbon atoms of the two chelating ligands
Configurational equilibrium and CD spectra under pressure of chiral octahedral complexes: Λ- and Δ-Cr[(-)(R,R)bdtp]3
No full textWe have studied the effect of pressure on the configurational inversion reaction at the metal centre of the chiral tris-(cyclic O,O'1(R),2(R)-dimethylethylene dithiophosphato) chromium(III) complexes, Λ(-)589Cr[(R,R)bdtp]3 and Δ(+)589Cr[(R,R)bdtp]3, in solutions of different solvents. We have observed positive or negative Cotton effects, assigned to the 4A2→4T2 transition of the metal ion in the visible region, and their evolution on increasing pressure. At equilibrium and at room conditions one observes a prevalence of the Δ-(R,R)(R,R)(R,R) diastereoisomer in CHCl3 or CH2Cl2 and of the Λ- one in THF. On increasing the pressure a change in the inversion equilibrium occurs, producing an increase in the concentration of the Λ-(R,R)(R,R)(R,R) form in all solvents
Induced CD on the d-d transitions of square planar MS4 chromophoric groups of Ni(II) complexes with enantiomeric dithiophosphate ligands: (+)(589)(-)(CD662)Ni[(R,R)bdtp](2) and (-)(589)(+)(CD662)Ni[(S,S)bdtp](2) (vol 4, pg 57, 1999)
No full textSynthesis, characterization and high pressure CD spectra of the OC-6 and SP-4 stereoisomeric complexes M[bdtp]3, M = Cr, Co, Rh, Ir, and Ni[bdtp]2
No full text
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
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