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Atmospheric pressure (AP) CVD of TiSe2films on glass substrates was achieved by reaction of di‐tert‐butylselenide and diethyl diselenide with TiCl4at 250–600 °C. All the films showed a TiSe2Raman pattern with bands at 133 cm–1and 198 cm–1. X‐ray diffraction (XRD) showed that the TiSe2films were crystalline with cell constants close to those expected: some preferred orientation was noted at higher deposition temperatures. Energy dispersive analysis by X‐rays (EDAX) gave a Ti:Se ratio close to 1:2 for all the films formed at 550 °C, and a Ti:Se ratio close to 1:1.5 for the film formed at 600 °C. The TiSe2films produced from diethyl diselenide and TiCl4had a powdery, purple, matte appearance whilst reaction with di‐tert‐butylselenide formed navy‐blue reflective films at deposition temperatures below 300 °C, and dark‐purple films at deposition temperatures above 350 °C. Scanning electron microscopy (SEM) showed that the films were composed of needle‐like crystals which became longer and thicker with increasing deposition temperature. After 60 days storage in air, Raman spectra of the films produced from diethyl diselenide and TiCl4revealed the presence of TiO2, whereas no change was noticed in the XRD and Raman spectra of the films produced from di‐tert‐butylselenide and TiCl4.

The reaction of gallium trichloride and methanol under atmospheric pressure chemical vapor deposition conditions leads to the production of gallium oxide thin films on a variety of substrates. Scanning electron microscopy (SEM) indicated that an island growth mechanism predominated. X-ray photoelectron spectroscopy (XPS) revealed binding energy shifts of 530.6 eV for O 1s and 20.3 eV for Ga 3d. The films were X-ray amorphous. Energy-dispersive X-ray analysis (EDXA) and electron probe microanalysis (EPMA) gave coherent elemental compositions, indicating that a single phase Ga2O3 was made, with negligible impurity levels. The films showed little optical reflectance (~10%) and 65−75% total transmission from 400 to 800 nm. Gas-sensing experiments indicated that the films responded best to a reducing gas at 450 °C.

The reaction between [Et2AlCl] and 1 equiv of HN(SiMe3)2 in CH2Cl2 afforded colorless crystals of [Et2AlCl{NH(SiMe3)2}] (1). In contrast, reaction of [Et2AlCl] with 1 equiv of HN(SiMe2H)2 or HN^tBu(SiMe3) resulted in the isolation of dimers, of the type [EtAlCl{NH(R‘)}]2 (2, R‘ = SiMe2H; 3, R‘ = ^tBu). Reaction of [Et3Al] with 1 equiv of HN(SiMe2H)2 or HN(SiMe3)2 yielded the expected dimeric complexes, [Et2Al{N(SiMe2H)2}]2 (4) and [Et2Al{N(SiMe3)2}]2 (5), via ethane elimination. The related reaction between [MeAlCl2] and HN^tBu(SiMe3) in CH2Cl2 solution resulted in the formation of the 1:1 adduct [MeAlCl2{NH2(^tBu)}] (6). The structures of compounds 1 and 6 have been determined by X-ray crystallography. In addition, the decomposition of 1 and 6 has been studied by thermal gravimetric analysis.

The dual-source atmospheric-pressure chemical vapor deposition of group IVb metal phosphide films from tetrakisdimethylamido(metal) and cyclohexylphosphine precursors is presented. Deposition took place at low temperatures (<500 °C), and nitrogen and carbon contamination of the films was negligible. The films had typical stoichiometric metal phosphide properties of high electrical conductivity, hardness, and chemical resistivity.

The reaction between [Me2AlCl] and 1 equiv of HN(SiMe2H)2 in CH2Cl2 afforded colorless crystals of [Cl(Me)Al{-NH(SiMe2H)}]2 (1). The structure of compound 1 has been determined and shows that the bridging NH(SiMe2H) groups adopt a mutually trans arrangement. The related reaction between [Me2AlCl] and 1 equiv of HN(SiMe2Ph)2 in CH2Cl2 solution resulted in the isolation of colorless crystals. An X-ray crystallographic study showed that the crystals consist of a mixture of [Cl(Me)2Al{NH(SiMe2Ph)2}] (2) and [Cl2(Me)Al{NH(SiMe2Ph)2}] (3) in a 1:4 ratio. The formation of compound 3 involves the exchange of one of the methyl groups attached to the aluminum atom with a chlorine atom.

Atmospheric pressure chemical vapor deposition of titanium phosphide coatings was achieved on glass substrates from the reaction of TiCl4 and RPH2 (R = t-Bu, Ph, Cy^hex) at 450−550 °C. The coatings show good uniformity, surface coverage, and adherence; they passed the Scotch brand tape test and could not be scratched with a brass scalpel. The leading edge of the titanium phosphide films was a deep blue while the bulk of the film was reflective and silver. Growth rates were on the order of 1 μm min^-1 at 550 °C. The films were crystalline, single phase with a hexagonal cell of a = 3.49(1) Å and c = 11.70(1) Å. Scanning electron microscopy (SEM) revealed surface morphologies consistent with an island growth mechanism. X-ray photoelectron spectroscopy (XPS) binding energy shifts were at 454.6 eV for Ti2p and at 128.6 eV for P2p. Energy-dispersive X-ray analysis (EDXA) and electron probe studies gave elemental ratios that were in agreement indicating in most cases slightly P-rich films, TiP1.2, with negligible chlorine incorporation. Raman spectra exhibited bands at 245, 320, and 410 cm^-1. Sheet resistance measurements showed typically 10−120 mΩ cm, indicating good conductivity. Rutherford backscattering showed a bulk composition of TiP1.2. Optically, the films showed high reflectivity at 1000 nm and showed 5−25% total transmission from 300 to 800 nm. Contact angle measurements were in the range 40−50° for the as made films these showed little change after 30 min of irradiation at 254 nm. All of the films showed negligible photocatalytic activity in the destruction of an overlayer of stearic acid.

The synthesis of [Bi2(biph)3] (5) and [PPN][BiCl2(biph)] (6) (biph = 2,2‘-biphenylylene, PPN = Ph3P&dbd;N&dbd;PPh3), the first structurally characterized biphenylylene complexes of bismuth (III), are described. Complex 5 crystallizes as a THF (tetrahydrofuran) solvate; each bismuth is three-coordinate with a trigonal pyramidal geometry. The solid state of 6 comprises separated [PPN]⁺ cations and [BiCl2(biph)]^- anions. The anion adopts a trigonal bipyramidal geometry at the bismuth; the axial sites are occupied by chloride ligands, and two of the three equatorial sites are occupied by ring carbon atoms.

Three cationic aryl−antimony and −bismuth complexes stabilized by intra- or intermolecular coordination have been prepared. Treatment of either SbAr2Cl or BiAr2Cl (Ar = 2-[(dimethylamino)methyl]phenyl, 2-(Me2NCH2)C6H4) with TlPF6 afforded [SbAr2][PF6] (1) or [BiAr2][PF6] (2), respectively. A related complex, [SbPh2{OP(NMe2)3}2][PF6] (5), stabilized by intermolecular coordination, was prepared via the reaction of SbPhCl2 with 2 equiv of TlPF6 in the presence of an excess of OP(NMe2)3. The X-ray crystal structures of compounds 1, 2, and 5 are described; the coordination geometry at the group 15 element center in each new compound was found to be distorted trigonal bipyramidal.

The reaction between equimolar quantities of BiCl3 and the silylphosphine P(SiMe3)3 in toluene or THF (tetrahydrofuran) solution affords a black precipitate with the composition of bismuth phosphide, BiP, which has been examined by EDXA, SEM, XPS, powder XRD, solid-state ³¹P NMR spectroscopy, and elemental analysis. Alternative possible routes to BiP involving the reactions between Na3P and BiCl3 and between Bi(NMe2)3 and P(SiMe3)3 have also been investigated, both of which afford black powders of composition close to BiP, although in the latter case there is some contamination with bismuth metal. Analogous reactions with either SbCl3 or AsCl3 and P(SiMe3)3 afford black and dark brown precipitates, respectively, which are formulated as the materials antimony phosphide, SbP, and arsenic phosphide, AsP, on the basis of similar analyses. Preliminary experiments have also shown that the related arsenides, BiAs and SbAs, can be prepared from reactions between either BiCl3 or SbCl3 and the silylarsine As(SiMe3)3, and that a ternary phase with the composition BiSbP2 is formed in the reaction between BiCl3, SbCl3, and P(SiMe3)3 in a 1:1:2 mole ratio. A material of composition close to elemental phosphorus is obtained from the reaction between PCl3 and P(SiMe3)3.