Thomas G. Hibbert

Definitive crystal structures of ortho-, meta- and para-carboranes: supramolecular structures directed solely by C–H⋯O hydrogen bonding to hmpa (hmpa = hexamethylphosphoramide)

Cocrystallisation of ortho-meta- and para-carboranes with hmpa (hexamethylphosphoramide) results in the isolation of 1 : 1 carborane:hmpa adducts which provide the first definitive X-ray structures of the unsubstituted carboranes as part of three very different C–H⋯O hydrogen-bonded supramolecular structures.

Synthesis and thermal decomposition studies of homo- and heteroleptic tin(IV) thiolates and dithiocarbamates: molecular precursors for tin sulfides

The syntheses and X-ray structures of novel heteroleptic thiolate/dithiocarbamate derivatives (Et2NCS2)2(RS)2Sn (R = Cy, CH2CF3) have been examined and their thermal decompositions compared with those of selected tin(II) and tin(IV) dithiocarbamates. The heteroleptic species decompose to SnS by initial elimination of RSSR to afford (Et2NCS2)2Sn and subsequent loss of [Et2NC(S)]2S. In contrast, (Et2NCS2)4Sn decomposes via [(Et2NCS2)2SnS]2, whose structure has been determined, and finally to SnS2 by sequential elimination of [Et2NC(S)]2S. The two families of compounds, (R2NCS2)4Sn and (Et2NCS2)2(RS)2Sn, thus provide single-source materials for bulk SnS2 and SnS, respectively, by virtue of their differing decomposition pathways. Preliminary CVD experiments with (Et2NCS2)2(CyS)2Sn are also reported.

Synthesis and structural characterisation of the first bis(bora)calixarene: a selective, bidentate, fluorescent fluoride sensorElectronic supplementary information (ESI) available: synthetic and spectroscopic details for the preparation of 3; details of the fluorescence titration of 3 with F? including details on the procedure used for calculation of binding constants; and details of the crystal structure refinement. See http://www.rsc.org/suppdata/cc/b4/b404937c/

A bis(bora)calixarene 3, the first lower-rim boron derivatised calixarene to be structurally characterised, is synthesised by the reaction of PhBCl2 with 4-tert-butylcalix[4]arene, and is demonstrated to be a sensitive and selective fluorescent fluoride sensor.

Atmospheric Pressure CVD of SnS and SnS2 on Glass

The atmospheric pressure chemical vapor deposition (APCVD) of SnS and SnS2 films from the reaction of SnCl4 and H2S was studied. The APCVD reaction of SnCl4 and H2S produced fast growth rates of good quality chlorine-free crystalline SnS films. SnS films were formed at 545 °C, while SnS2 films were produced at lower temperatures.

Deboronation of ortho-carborane by an iminophosphorane: crystal structures of the novel carborane adduct nido-C2B10H12·HNP(NMe2)3 and the borenium salt [(Me2N)3PNHBNP(NMe2)3]2O2+(C2B9H12–)2

The structures of the adduct nido-C2B10H12·HNP(NMe2)3 and the borenium salt [(Me2N)3PNHBNP(NMe2)3]2O2+(C2B9H12–)2, both obtained from 1,2-C2B10H12 and HNP(NMe2)3, were determined by X-ray crystallography; the adduct represents the first structurally determined carborane of its type, a possible intermediate in the well known conversion of closo-1,2-C2B10H12 into the nido-7,8-C2B9H12– anion by bases.

Designing precursors for the deposition of tin sulphide thin films

This paper reviews the work carried out by the authors over the last three years on the deposition of tin sulphide films. Particular emphasis is placed on the design and limitations of single-source precursors for these films. Simple homoleptic thiolates Sn(SR)(4) only generate tin sulphides in combination with H2S, otherwise Sn3O4 is produced by in situ formation of Sn(0) and subsequent oxidation. This problem is overcome by the use of chelating dithiolates. The decomposition of mixed ligand (RS)(2)Sn(S2CNEt2)(2) are also described, as are the synthesis and structures of mixed metal thiolates (Ph3PP)AuSSnCy3 and PhHgSSnCy3, potential precursors for ternary tin-containing sulphides.

Structural distortions in homoleptic (RE)(4)A (E = O, S, Se; A = C, Si, Ge, Sn): implications for the CVD of tin sulfides

The structures of Sn(SBut)4 and Sn(SCy)4 have been determined and adopt S4 and D2 conformations respectively; the anion [(PhS)Sn3]−, as its Ph4P+ salt, has a structure approaching Cs symmetry. In all three compounds, there are large variations in the ∠S–Sn–S within the same molecule, which have been rationalised in terms of the C–S–Sn–S–C conformations. For Sn(SR)4, the ∠S–Sn–S increases as the conformations change from trans, trans to trans, gauche and gauche, gauche, as the number of eclipsed lone pairs decreases and this rationale is shown to be applicable to a variety of A(ER)4 (A = C, Si, Ge, Sn; E = O, S, Se) and related [Mo(SR)4, Ga(SR)4−] systems. AM1 calculations have been used to model the ∠S–Sn–S magnitudes and also provide insights into the decomposition mechanisms of these and related species which are relevant to chemical vapour deposition processes.