ABSTRACT
The synthesis and X-ray crystal structures of the diborane(4) isomers 1,1-B(2){1,2-(NH)(2)C(6)H(4)}(2) and 1,2-B(2){1,2-(NH)(2)C(6)H(4)}(2) are described together with the results of quantum chemical calculations which shed light on their relative stabilities and degree of aromaticity. Spectroscopic data are also provided for both isomers of the 4-methyl aryl derivative. The compound 1,1-B(2){1-O-2-(NH)C(6)H(4)}(2) has also been prepared and structurally characterised but no evidence was obtained for the corresponding 1,2-isomer. The compound 1,1-B(2){1,2-(NH)(2)C(6)H(4)}(2) forms a co-crystal with TCNQ, the structure of which is also reported.
ABSTRACT
Angle-dependent magnetoresistance measurements are used to determine the isotropic and anisotropic components of the transport scattering rate in overdoped Tl2Ba2CuO6+delta for a range of Tc values between 15 and 35 K. The size of the anisotropic scattering term is found to scale linearly with Tc, establishing a link between the superconducting and normal state physics. A comparison with results from angle resolved photoemission spectroscopy indicates that the transport and quasiparticle lifetimes are distinct.