Author
Biswarup Sarkar
Bio: Biswarup Sarkar is an academic researcher from University of Calcutta. The author has contributed to research in topics: Schiff base & Carboxylate. The author has an hindex of 9, co-authored 12 publications receiving 313 citations.
Papers
More filters
TL;DR: Structural, theoretical, and experimental magnetic data indicate that the higher the degree of distortion, the greater the ferromagnetic coupling.
Abstract: Three new trinuclear copper(II) complexes, [(CuL(1))(3)(micro(3)-OH)][ClO(4)](2).3 H(2)O (1), [(CuL(2))(3)(micro(3)-OH)][ClO(4)](2).H(2)O (2), and [(CuL(3))(3)(micro(3)-OH)][ClO(4)](2).7 H(2)O (3) have been synthesized from the three tridentate Schiff bases HL(1), HL(2), and HL(3) (HL(1)=6- aminomethyl-3-methyl-1-phenyl-4-azahex-2-en-1-one, HL(2)=6-aminoethyl-3-methyl-1-phenyl-4-azahex-2-en-1-one, and HL(3)=6-aminodimethyl-3-methyl-1-phenyl-4-azahex-2-en-1-one). They have been characterized by X-ray crystallography and IR and UV spectroscopy, and their magnetic properties have been investigated. All the compounds contain a partial cubane [Cu(3)O(4)] core consisting of the trinuclear unit [(CuL)(3)(micro(3)-OH)](2+), perchlorate ions, and water molecules. In each of the complexes, the copper atoms are five-coordinate with a distorted square-pyramidal geometry except complex 1, in which one of the Cu(II) of the trinuclear unit is weakly coordinated to one of the perchlorate ions. Magnetic measurements performed in SQUID MPMS-XL7 using polycrystalline samples at an applied field of 2 kOe indicate a global intramolecular ferromagnetic coupling. Magnetostructural correlations have been calculated on the basis of theoretical models without symmetry restriction. Continuous shape measurements are an appropriate tool for establishing the degree of distortion of the Cu(II) from square-planar geometry. Structural, theoretical, and experimental magnetic data indicate that the higher the degree of distortion, the greater the ferromagnetic coupling.
66 citations
TL;DR: Two tridentate Schiff bases, HL1(6-amino-3-methyl-1-phenyl-4-azahex-2-en-1one) and HL2(6amino,3,6-dimethyl-1-,4-hexhexhex 2-en1-one) on reaction with copper perchlorate in the presence of triethyl amine yielded two new trinuclear copper(II) complexes, [(CuL1)3(μ3-OH)](ClO4)2) and [(cuL2)
57 citations
TL;DR: In this paper, four new cadmium(II) complexes with hexamine (hmt) and monocarboxylate ions, benzoate (bz), phenylacetate (pa), or acetate (ac), were synthesized and characterized structurally.
Abstract: Four new cadmium(II) complexes [Cd2(bz)4(H2O)4(μ2-hmt)]·Hbz·H2O (1), [Cd3(bz)6(H2O)6(μ2-hmt)2]·6H2O (2), [Cd(pa)2(H2O)(μ2-hmt)]n (3), and {[Cd3(ac)6(H2O)3(μ3-hmt)2]·6H2O}n (4) with hexamine (hmt) and monocarboxylate ions, benzoate (bz), phenylacetate (pa), or acetate (ac) have been synthesized and characterized structurally. Structure determinations reveal that 1 is dinuclear, 2 is trinuclear, 3 is a one-dimensional (1D) infinite chain, and 4 is a two-dimensional (2D) polymer with fused hexagonal rings consisting of CdII and hmt. All the CdII atoms in the four complexes (except one CdII in 2) possess seven-coordinate pentagonal bipyramidal geometry with the various chelating bidentate carboxylate groups in equatorial sites. One of the CdII ions in 2, a complex that contains two monodentate carboxylates is in a distorted octahedral environment. The bridging mode of hmt is μ2- in complexes 1−3 but is μ3- in complex 4. In all complexes, there are significant numbers of H-bonds, C−H/π, and π−π interactions wh...
41 citations
TL;DR: Two tridentate N,N,O donor bases, HL1 (4-ethylamino-ethylimino)-pentan-2-one) and HL2 (3-(2-amino-propylimino)1-phenyl-butan-1-one), were shown to have a very weak antiferromagnetic coupling for both complexes U = -0.56 and -1.19 cm(-1) for 1 and 2, respectively as mentioned in this paper.
41 citations
TL;DR: In this article, three new copper(II) complexes with three Schiff base ligands are synthesized and structurally characterized by X-ray crystallography, and all three complexes exhibit reversible cyclic voltammetric responses in acetonitrile solution corresponding to the CuII/CuI redox process.
34 citations
Cited by
More filters
2,430 citations
TL;DR: The International Tables for X-ray Crystallography (ITC) as mentioned in this paper were published by the International Union of Crystallographers (IUC) for the first time in 1952.
Abstract: International Tables for X-Ray Crystallography (Published for the International Union of Crystallography.) Vol. 1: Symmetry Groups. Edited by Norman F. M. Henry and Kathleen Lonsdale. Pp. xi + 558. (Birmingham: Kynoch Press, 1952.) 105s.
691 citations
TL;DR: In this paper, the design and properties of β-diketones or β-ketophenols and related complexes, together with their evolution into more sophisticated linear or tridimensional polymeric systems, are reviewed.
272 citations
TL;DR: A review of the recent developments of unsymmetrically-substituted multidentate Schiff bases whose steric and electronic characteristics are easily manipulated by selecting suitable condensing aldehydes or ketones and primary amines, and on their metal complexes can be found in this article.
250 citations
TL;DR: All of the compounds investigated for their antimicrobial activities against the fungus, Candida albicans, and against Gram-positive and Gram-negative bacteria were found to have excellent anti-Candida activity but were inactive against Staphylococcus aureus and Escherichia coli.
188 citations