117679-69-3Relevant academic research and scientific papers
The central atom size effect on the structure of group 14 tetratolyls
Ng, Maggie C. C.,Craig, Donald J.,Harper, Jason B.,Van-Eijck, Lambert,Stride, John A.
, p. 6569 - 6572 (2009)
The tetraphenyl derivatives of the Group 14 elements are of great potential interest as supramolecular constructs in extended porous networks. The tetratolyl Group 14 compounds were synthesized by using a general reaction scheme involving the nucleophilic addition of an organometallic reagent to the electrophilic center of the Group 14 element. The tetrachloride derivatives were used for the synthesis of the silane, germane and stannane compounds. Sn(Tol)4 was found to have tunnel splittings much smaller than the minimum line width available on IN16, whereas the lighter analogues displayed a remarkable size effect of the central atom. The tunneling peaks were observed to persist up to around 30 K, before softening and extending into the limit of quasielastic diffusion in which the rotors undergo thermally excited rotation.
Central-atom size effects on the methyl torsions of group XIV tetratolyls
Ng, Maggie C. C.,Harper, Jason B.,Stampfl, Anton P. J.,Kearley, Gordon J.,Rols, Stephane,Stride, John A.
, p. 13018 - 13024 (2013/01/15)
The Group XIV tetratolyl series X(C6H4-CH 3)4 (X=C, Si, Ge, Sn, Pb) were studied by using inelastic neutron scattering to measure the low-energy phonon spectra to directly access the methyl-group torsional modes. The effect of increased molecular radius as a function of the size of the central atom was shown to have direct influence on the methyl dynamics, reinforced with the findings of molecular dynamics and contact surface calculations, based upon the solid-state structures. The torsional modes in the lightest analogue were found to be predominantly intramolecular: the Si and Ge analogues have a high degree of intermolecular methyl-methyl group interactions, whilst the heaviest analogues (Sn and Pb) showed pronounced intermolecular methyl interactions with the whole phonon bath of the lattice modes. Size matters! The size of the central atom in the Group XIV tetratolyls was shown to determine the solid-state structures courtesy of the effect that it has on the overall size of the molecules (see figure). Because the outer-most methyl groups enter into close intermolecular interactions (for the Si and Ge analogues), the structure is driven to lower symmetry; as a consequence, the smallest (C) and largest (Sn and Pb) analogues are isostructural. Copyright
EPR, 1H, and 13C ENDOR Studies of a Quintet-State 13C-Labeled Galvinoxyl-Type Tetraradical
Kirste, Burkhard,Grimm, Michael,Kurreck, Harry
, p. 108 - 114 (2007/10/02)
The syntheses of unlabeled and fourfold 13C-labeled tetraphenylmethane tetrakisgalvinols are described.Different paramagnetic species, i.e., a double-state monoradical, a triplet-state biradical, a quartet-state triradical, a quintet-state tetraradical, c
