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Morsy A. M. Abu-Youssef

Other affiliations: Graz University of Technology
Bio: Morsy A. M. Abu-Youssef is an academic researcher from Alexandria University. The author has contributed to research in topics: Crystal structure & Molecule. The author has an hindex of 28, co-authored 86 publications receiving 2353 citations. Previous affiliations of Morsy A. M. Abu-Youssef include Graz University of Technology.


Papers
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TL;DR: In this article, the reaction of sodium azide with manganese(II) and pyridine derivatives such as 2-bzpy and 3-5lut led to the one-dimensional systems cis-[Mn(2bzppy)(N3)2]n (1), trans-[mn(3-bppy)2(N3]n 2]n n (2), and cis-[mns(3ppy(n3lut)2[n 3]n 3 ]n (3])n (
Abstract: Reaction of sodium azide with manganese(II) and pyridine derivatives such as 2-bzpy, 3-bzpy, and 3,5lut (2-benzoylpyridine, 3-benzoylpyridine, and 3,5-dimethylpyridine, respectively) led to the one-dimensional systems cis-[Mn(2-bzpy)(N3)2]n (1), trans-[Mn(3-Bzpy)2(N3)2]n (2), and cis-[Mn(3,5lut)2(N3)2]n (3). Compound 1 crystallizes in the P21/n group: a = 14.413(4) A, b = 16.157(4) A, c = 18.478(5) A, and Z = 12. Compound 2 crystallizes in the C2/c group: a = 14.179(5) A, b = 9.698(4) A, c = 34.351(12) A, and Z = 8. Compound 3 crystallizes in the P21/n group: a = 13.552(6) A, b = 7.730(3) A, c = 16.554(6) A, and Z = 4. Structural determination shows a chain with double μ1,1 azido bridges for 1, an alternating system with double μ1,1 and μ1,3 azido bridges for 2, and finally a chain with double μ1,3 azido bridges for 3. Susceptibility data show ferromagnetic coupling for 1, antiferromagnetic coupling for 3, and alternating ferro−antiferromagnetic interactions for 2. EPR data measured on powdered samples...

173 citations

Journal ArticleDOI
TL;DR: A model of the Heisenberg chain, comprising classical spins coupled through alternating exchange interactions J1J1J2... is proposed to describe the magnetic behavior.
Abstract: The reaction of manganese(II) and pyridine derivatives such as 3-methylpyridine (3-Mepy) and 3,4-dimethylpyridine (3,4-Dmepy) led to the new one-dimensional systems trans-[Mn(3-Mepy)2(N3)2]n (1) and trans-[Mn(3,4-Dmepy)2(N3)2]n (2). Compound 1 crystallizes in the monoclinic system, space group P2(1)/n, a = 11.201(3) A, b = 14.499(4) A, c = 14.308(4) A, Z = 6, and compound 2 crystallizes in the triclinic system, space group P1, a = 11.502(4) A, b = 14.246(5) A, c = 16.200(8) A, Z = 6. The two compounds show the same general one-dimensional arrangement of double azido bridges between neighboring manganese atoms with the unprecedented -Mn-(mu(1,3)-N3)2-Mn-(mu(1,3)-N3)2-Mn-(mu(1,1)-N3)2-Mn- sequence. Susceptibility and magnetization measurements reveal a ferrimagnetic-like behavior derived from the topology of the chain. A model of the Heisenberg chain, comprising classical spins coupled through alternating exchange interactions J1J1J2... is proposed to describe the magnetic behavior.

139 citations

Journal ArticleDOI
TL;DR: In this article, two polymeric manganese-azido systems with formula Cs(n)-[[Mn(N3)3]n] (1) and [[N(C2H5)4]n][[Mn2-(N3)]5(H2O)]n] were synthesized and structurally characterised.
Abstract: Two new polymeric manganese-azido systems with formula Cs(n)-[[Mn(N3)3]n] (1) and [[N(C2H5)4]n][[Mn2-(N3)5(H2O)]n] (2) were synthesised and structurally characterised. Compound 1 crystallises in the P2(1)/n group and consists of a three-dimensional system with end-to-end and end-on azido bridges with the caesium atoms in the holes of the net. Magnetically, compound 1 is a rare case of a three-dimensional network with alternate ferro-antiferromagnetic interactions. Compound 2 crystallises in the P1 group and consists of double chains of manganese atoms bridged by end-on and, the exceptional, (mu-1,1,1)-azido bridges. Magnetically, compound 2 shows net ferromagnetic behaviour. Exact fit of the magnetic data was performed for the two compounds by means of Monte Carlo simulations based on the Metropolis algorithm on sets of 10 x 10 x 10 (1) and 1 x 1 x 320 (2) S = 5/2 classical spin centres.

139 citations

Journal ArticleDOI
TL;DR: The reported Mn(II)-azide system is the first example of a two-dimensional homometallic ferrimagnet, in which the magnetic properties are due exclusively to topological reasons related with the coordination mode of the bridging ligands.

96 citations


Cited by
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[...]

08 Dec 2001-BMJ
TL;DR: There is, I think, something ethereal about i —the square root of minus one, which seems an odd beast at that time—an intruder hovering on the edge of reality.
Abstract: There is, I think, something ethereal about i —the square root of minus one. I remember first hearing about it at school. It seemed an odd beast at that time—an intruder hovering on the edge of reality. Usually familiarity dulls this sense of the bizarre, but in the case of i it was the reverse: over the years the sense of its surreal nature intensified. It seemed that it was impossible to write mathematics that described the real world in …

33,785 citations

01 Feb 1995
TL;DR: In this paper, the unpolarized absorption and circular dichroism spectra of the fundamental vibrational transitions of the chiral molecule, 4-methyl-2-oxetanone, are calculated ab initio using DFT, MP2, and SCF methodologies and a 5S4P2D/3S2P (TZ2P) basis set.
Abstract: : The unpolarized absorption and circular dichroism spectra of the fundamental vibrational transitions of the chiral molecule, 4-methyl-2-oxetanone, are calculated ab initio. Harmonic force fields are obtained using Density Functional Theory (DFT), MP2, and SCF methodologies and a 5S4P2D/3S2P (TZ2P) basis set. DFT calculations use the Local Spin Density Approximation (LSDA), BLYP, and Becke3LYP (B3LYP) density functionals. Mid-IR spectra predicted using LSDA, BLYP, and B3LYP force fields are of significantly different quality, the B3LYP force field yielding spectra in clearly superior, and overall excellent, agreement with experiment. The MP2 force field yields spectra in slightly worse agreement with experiment than the B3LYP force field. The SCF force field yields spectra in poor agreement with experiment.The basis set dependence of B3LYP force fields is also explored: the 6-31G* and TZ2P basis sets give very similar results while the 3-21G basis set yields spectra in substantially worse agreements with experiment. jg

1,652 citations

Journal ArticleDOI
TL;DR: A comparison study of 3D Networks Based on Polypyrazolates, Metal 1,2,4-Triazolate Frameworks, and Univalent Coinage-Metal Tetrazolate Framework 1025.
Abstract: 2.1.2. Low Topology/Framework Density 1003 2.1.3. Side Group Directed Superstructures 1003 2.2. Synthesis Considerations 1003 2.3. Special Properties 1004 3. Metal Imidazolate Frameworks 1004 3.1. Chains and Rings 1004 3.2. Zeolitic and Zeolite-like Frameworks 1006 3.2.1. SOD-Type Zinc(II) 2-Methylimidazolate 1007 3.3. Nonporous 4-Connected Networks 1010 3.4. Polyimidazolates 1011 4. Metal Pyrazolate Frameworks 1011 4.1. Clusters and Chains 1011 4.2. 3D Networks Based on Polypyrazolates 1012 5. Metal 1,2,4-Triazolate Frameworks 1014 5.1. Simple 3-Connected Networks 1015 5.2. Quasi-Imidazolates 1018 5.3. With Coordinative Substituents 1019 5.4. With Secondary Counterions and/or Ligands 1021 6. Metal 1,2,3-Triazolate Frameworks 1023 7. Metal Tetrazolate Frameworks 1025 7.1. Univalent Coinage-Metal Tetrazolate Frameworks 1025

1,433 citations

Journal ArticleDOI
TL;DR: The state of the art in the field of antimicrobial polymeric systems during the last decade is described in this paper, where a classification of the different materials is carried out dividing basically those synthetic polymers that exhibit antimicrobial activity by themselves; those whose biocidal activity is conferred through their chemical modification; those that incorporate antimicrobial organic compounds with either low or high molecular weight; and those that involve the addition of active inorganic systems.

1,063 citations

Journal ArticleDOI
TL;DR: In this paper, a review of metal-organic frameworks (MOFs) and porous coordination polymers (PCPs) with selected examples of their structures, concepts for linkers, syntheses, post-synthesis modifications, metal nanoparticle formations in MOFs, porosity and zeolitic behavior for applications in gas storage for hydrogen, carbon dioxide, methane and applications in conductivity, luminescence and catalysis.
Abstract: This review (over 380 references) summarizes metal–organic frameworks (MOFs), Materials Institute Lavoisier (MILs), iso-reticular metal–organic frameworks (IR-MOFs), porous coordination networks (PCNs), zeolitic metal–organic frameworks (ZMOFs) and porous coordination polymers (PCPs) with selected examples of their structures, concepts for linkers, syntheses, post-synthesis modifications, metal nanoparticle formations in MOFs, porosity and zeolitic behavior for applications in gas storage for hydrogen, carbon dioxide, methane and applications in conductivity, luminescence and catalysis.

1,017 citations