XMCD studies of thin Co films on BaTiO3.

Different layer thicknesses of cobalt ranging from 2.6 Å (1.5 ML) up to 55 Å (30.5 ML) deposited on ferroelectric BaTiO3 have been studied regarding their magnetic behavior. The layers have been characterized using XMCD spectroscopy at remanent magnetization. After careful data analysis the magnetic moments of the cobalt could be determined using the sum rule formalism. There is a sudden and abrupt onset in magnetism starting at thicknesses of 9 Å (5 ML) of cobalt for measurements at 120 K and of 10 Å (5.5 ML) if measured at room temperature. Initial island growth and subsequent coalescence of Co on BaTiO3 is suggested to explain the sudden onset. In that context, no magnetically dead layers are observed.

Diethyl [(5-chloro-2-hydroxy-anilino)(4-chloro-phen-yl)meth-yl]phospho-nate.

In the title compound, C(17)H(20)Cl(2)NO(4)P, the P atom is bonded in a distorted tetra-hedral environment. The dihedral angle between the two benzene rings is 80.5 (1)°. In the crystal structure, inter-molecular O-H⋯O and N-H⋯O hydrogen bonds link pairs of mol-ecules into centrosymmetric dimers. These dimers, are in turn, linked by weak inter-molecular C-H⋯O hydrogen bonds into one-dimensional chains along [010]. Additional stabilization is provided by very weak C-H⋯Cl inter-actions.

3-(6-Methyl-2-pyrid-yl)-2-phenyl-3,4-dihydro-1,3,2-benzoxaza-phosphinine 2-oxide.

In the title compound, C(19)H(17)N(2)O(2)P, the six-membered 1,3,2-oxaza-phosphinine ring adopts a boat conformation with the phosphoryl O atom in an equatorial position. The dihedral angle between the 6-methyl-2-pyridyl and phenyl groups is 75.5 (1)°. These substituents are trans to each other, and are oriented at angles of 57.2 (1) and 74.8 (1)°, respectively, to the benzene ring. The crystal structure is stabilized by intra- and inter-molecular hydrogen bonds. The phosphoryl O atom participates in inter-molecular C-H⋯O inter-actions with the neighbouring mol-ecules, forming centrosymmetric R(2) (2)(14) dimers.

6-Bromo-2-(4-nitro-phen-oxy)-3-(1-phenyl-ethyl)-3,4-dihydro-1,3,2-benzoxaza-phosphinine 2-oxide.

In the title compound, C(21)H(18)BrN(2)O(5)P, the six-membered oxaza-phosphinine ring is in a twist-boat conformation. One of the phosphoryl O atoms is in an equatorial configuation while the other is axial with respect to the oxaza-phosphinine ring. The mean planes of the benzene ring to which the nitro group is attached and the phenyl ring form a dihedral angle of 83.5 (1)°. In the crystal structure, weak inter-molecular C-H⋯O hydrogen bonds link the mol-ecules into chains along [100].

Diethyl [(4-bromo-phen-yl)(5-chloro-2-hydroxy-anilino)meth-yl]phospho-nate.

In the title compound, C(17)H(20)BrClNO(4)P, inter-molecular C-H⋯O and N-H⋯O hydrogen bonds form centrosymmetric R(2) (2)(10) dimers linked through O-H⋯O inter-molecular hydrogen bonds, which form centrosymmetric R(2) (2)(16) dimers. All these hydrogen bonds form chains along [010]. In addition, the crystal structure is stabilized by weak C-H⋯Br hydrogen bonds. The very weak intramolecular N-H⋯O interaction forms a five-membered ring.

2,4,8,10,13-Penta-methyl-6-phenyl-13,14-dihydro-12H-6λ-dibenzo[d,i][1,3,7,2]dioxaza-phosphecin-6-thione.

In the title compound, C(25)H(28)NO(2)PS, the cyclo-decene ring exhibits a crown conformation. The two dimethyl-benzene rings which are fused symmetrically on either side of the ten-membered ring, make dihedral angles of 20.2 (1) and 18.0 (1)°. The phenyl ring substituted at P is perpendicular to the heterocyclic ring, making a dihedral angle of 88.4 (1)°. The crystal structure is stabilized by very weak intra-molecular C-H⋯O hydrogen bonding.

3-(6-Methyl-2-pyrid-yl)-2-phen-oxy-3,4-dihydro-1,3,2-benzoxaza-phosphirine 2-oxide.

In the title compound, C(19)H(17)N(2)O(3)P, the six-membered 1,3,2-oxaza-phospho-rine ring adopts a twist-boat conformation with the phosphoryl O atom in an equatorial position. The P=O(oxide) bond length is 1.457 (1) Šand the average value of the P-O distances is 1.588 Å. The crystal structure is stabilized by C-H⋯O and C-H⋯π inter-actions.