Search

Dioxotetrafluoromolybdate, (NH4)2MoO2F4, was synthesized in a single-crystal form and its structures [(I) at 297 K and (II) at 223 KI were determined by X-ray diffraction. Two independent states of a cis-MoO2F4 octahedron are character- istic of static and dynamic disorder in structure (I). The dynamically disordered Mo atom is displaced from the symmetry axis producing four possible orientations of an anion that allow O and F atoms to be identified in separate orientations owing to the inherent differences between the Mo-O and Mo-F bonding. After the phase transition at lower temperature, (I) transforms into the statically disordered structure (II) with three possible orientations of the cis-MoO2F4 octahedron. In this case, it also seemed possible to distinguish between O and F atoms on a local scale. H atoms of two independent NH4 groups in (II) which form bifurcated N-H∙∙∙F(O) hydrogen bonds were localized. [ABSTRACT FROM AUTHOR]

Dioxotetrafluoromolybdate, (NH4)2MoO2F4, was synthesized in a single-crystal form and its structures [(I) at 297 K and (II) at 223 KI were determined by X-ray diffraction. Two independent states of a cis-MoO2F4 octahedron are character- istic of static and dynamic disorder in structure (I). The dynamically disordered Mo atom is displaced from the symmetry axis producing four possible orientations of an anion that allow O and F atoms to be identified in separate orientations owing to the inherent differences between the Mo-O and Mo-F bonding. After the phase transition at lower temperature, (I) transforms into the statically disordered structure (II) with three possible orientations of the cis-MoO2F4 octahedron. In this case, it also seemed possible to distinguish between O and F atoms on a local scale. H atoms of two independent NH4 groups in (II) which form bifurcated N-H∙∙∙F(O) hydrogen bonds were localized. [ABSTRACT FROM AUTHOR]

The article presents a study on the crystal structure of orthorhombic aluminium oxyfluoride, AIOF. It presents the atom-labelling scheme of the AIOF structure and the octahedral ordering in AIOF crystals. The authors note that AlF3 was added in a 2-5% excess to the starting reaction mixture because of its high volatility and state that the crystallization temperature was 1140 Kelvin.

The title compound, [MnPt(C5H5)(C8H6)(C18H15P)2(CO)2], is a dinuclear heterometallic Mn—Pt( μ-C=CHPh) complex obtained as a product of the addition of [Pt(PPh3)]2 to ( η5-C5H5)(CO)2Mn=C=CHPh. The two metal atoms are bridged by the μ-phenylvinylidene ligand and semibridged by a carbonyl group. The central fragment of the molecule is an almost planar methylenedimetallacyclopropane Mn—Pt( μ-C=CHPh) system. The coordination of the Mn atom is formed by two parallel planes: the first plane consists of three carbonyl C atoms and the second is the cyclopentadienyl plane. A distorted square-planar coordination of the Pt atom is formed by two P atoms of PPh3 and C atoms of the semi-bridging and C=CHPh ligands. [ABSTRACT FROM AUTHOR]