Entity

Time filter

Source Type

Rabat, Morocco

Naji S.,Mohammed V University | Naji S.,Ibb University | Ziti S.,Mohammed V University | Belhaj A.,Sultan Moulay Slimane University | And 7 more authors.
Journal of Superconductivity and Novel Magnetism | Year: 2015

Borrowing ideas from Lie algebras, we propose a new nanotube model based on a double hexagonal geometry appearing in the G2 Lie symmetry. This structure involves two hexagons of unequal side length at angle 30 ∘ producing (3×3)R30∘$(\sqrt {3}~\times ~\sqrt {3})R30~^{\circ }$ and (1 × 1) geometries. In this configuration system, the principal unit cell contains 12 sites instead of only 6 ones, arising in the single hexagonal structure on which the graphene-like models are based. More precisely, we engineer a superlattice model based on periodic bilayers consisting of particles with the spins σ=±12$\sigma =\pm \frac {1}{2}$ having two possible states, placed at sites of the double hexagonal structure. Then, we investigate the phase diagrams and the magnetic properties using the mean field method. In particular, we find six stable phases required by a global Z2 symmetry associated with the spin values placed at the site of the G2 double hexagonal structure. © 2015, Springer Science+Business Media New York.

Al Mamari K.,Mohammed V University | Ennajih H.,Mohammed V University | Bouhfid R.,Institute of Nanomaterials and Nanotechnology MAScIR | Essassi E.M.,Mohammed V University | And 2 more authors.
Acta Crystallographica Section E: Structure Reports Online | Year: 2012

In the title compound, C38H34Cl2N 4O2, the piperazine ring adopts a chair conformation. The pyrrolidine rings that are fused to the piperazine ring adopt envelope conformations (in which the C atoms connecting the two rings represent the flap). The indoline ring systems are approximately planar (r.m.s. deviations = 0.026 and 0.034 Å) and are aligned at a dihedral angle of 54.98 (3)°.

Al Mamari K.,Mohammed V University | Ennajih H.,Mohammed V University | Bouhfid R.,Institute of Nanomaterials and Nanotechnology MAScIR | Essassi E.M.,Mohammed V University | And 2 more authors.
Acta Crystallographica Section E: Structure Reports Online | Year: 2012

The molecule of the title compound, C30H32N 4O2, lies on a twofold rotation axis that passes through the mid-points of the C - C bonds of the piperazine ring, which adopts a chair conformation. The pyrrolidine ring that is fused to the piperazine ring adopts an envelope conformation (in which the N atom represents the flap). The indoline fused-ring system is nearly planar (r.m.s. deviation = 0.044 Å); the two symmetry-related indoline fused-rings systems are aligned at 71.44 (3)°.

Al Mamari K.,Mohammed V University | Ennajih H.,Mohammed V University | Bouhfid R.,Institute of Nanomaterials and Nanotechnology MAScIR | Essassi E.M.,Mohammed V University | And 2 more authors.
Acta Crystallographica Section E: Structure Reports Online | Year: 2012

In the molecule of the title compound, C30H30Br 2N4O2, the piperazine ring adopts a chair conformation. The pyrrolidine rings that are fused to the piperazine ring adopt envelope conformations (in which the N atom represents the flap). The indoline fused-ring systems are nearly planar (r.m.s. deviations = 0.009 and 0.019 Å); the two fused rings are aligned at 60.63 (6)°.

Rida M.,Mohammed V University | Alsubari A.,Mohammed V University | Essassi E.M.,Mohammed V University | Zouihri H.,Institute of Nanomaterials and Nanotechnology MAScIR | And 2 more authors.
Acta Crystallographica Section E: Structure Reports Online | Year: 2011

In the title compound, C17H16N2O 3, the seven-membered diazepine ring adopts a boat conformation with the hy-droxy-substituted C atom at the prow and fused benzene ring C atoms at the stern. The phenyl substituent occupies an equatorial position. The amino group of the ring system is a hydrogen-bond donor to the oxo O atom of an inversion-related molecule, and the hy-droxy group is a hydrogen-bond donor to the acetyl O atom of another inversion-related molecule. The two hydrogen bonds generate a ribbon motif parallel to [10 ] in the crystal structure.

Discover hidden collaborations