Şehriman Atalay

Calculations of overlap integrals using recurrence-based algorithms

Abstract The aim of this study is to present a new algorithm and analytical formulae for calculation of overlap integrals with the same screening parameters over Slater-type orbitals based on recurrence relations for the basic coefficient G nlm , n ′ l ′ m ′ NLM . By using these integrals we have subsequently calculated overlap integrals for the values of principal quantum numbers up to 55 and for arbitrary values of parameters p and t .

(E)-4-Bromo-2-[(4-ethyl­phen­yl)imino­meth­yl]phenol

In the title compound, C15H14BrNO, the dihedral angle between the two benzene rings is 43.99 (2)°. The molecular conformation is influenced by an intramolecular O—H⋯N hydrogen bond.

4-(2-Iso­propyl-5-methyl­phenoxy)­phthalo­nitrile

In the title compound, C18H16N2O, two benzene rings are connected by an O atom, and the dihedral angle between them is 86.83 (1)°. The C—O—C angle is 118.50 (14)°.

2-[(2-Bromo-phen-yl)imino-meth-yl]-6-methyl-phenol.

In the title compound, C14H12BrNO, is a Schiff base which adopts the phenol–imine tautomeric form in the solid state. The dihedral angle between the two aromatic rings is 34.26 (9)° and an intramolecular O—H⋯N hydrogen bond generates an S(6) ring.

4‐(2‐Bromo‐4‐chloro­phen­oxy)phthalonitrile

The title phthalonitrile derivative, C14H6BrClN2O, contains two aromatic rings, which are almost perpendicular.

4-(3-Bromo­benzyl­idene­amino)-3-(4-chloro­benzyl)-4,5-di­hydro-1H-1,2,4-triazol-5-one

The title compound, C16H12BrClN4O, contains two benzene rings and a triazole ring which is substituted at the 1,2,4-positions. The crystal structure of (I) is stabilized by N—H⋯O and π–π stacking interactions.

Benzyl 2‐(3,4‐di­cyano­phenoxy)­benzoate

The title compound, C22H14N2O3, contains three planar aromatic rings arranged in a U-shaped conformation. There are weak intermolecular C—H⋯O hydrogen-bond interactions stabilizing the crystal structure.

4-(2-Benzoyl-5-methoxyphenoxy)benzene-1,2-dicarbonitrile

The title compound, C22H14N2O3, contains three benzene rings, pairs of which form dihedral angles of 55.37 (5), 68.47 (4) and 82.82 (4)°. The average C—O—C angle is 119.0 (1)°.

4-(2-Methoxy-4-methyl­phenoxy)­phthalo­nitrile

In the title compound, C16H12N2O2, the dihedral angle between the two benzene rings is 85.53 (5)°. The crystal structure is stabilized by intermolecular C—H⋯O hydrogen bonds and C—H⋯π interactions.

EPR Studies of VO2+ in Ba(ClO4) 2 ・3H2O Single Crystals

The results of an electron paramagnetic resonance (EPR) study of vanadyl ion VO2+ doped in single crystals of Ba(ClO4)2 - 3 H2O are reported. The spectra indicated the presence of two substitutional and interstitial sites depending on the orientation. The spin-Hamiltonian parameters were determined from single crystal and powder EPR data. These parameters were found to be axial symmetric for the powder sample, whereas they showed deviations from axial symmetry for the single crystal