The low temperature specific heat of a single crystal of La<Subscript>2</Subscript>CuO<Subscript>4+δ</Subscript> in magetic fields of 0, 2 and 4 Tesla

A single crystal of La₂CuO₄ was made superconducting after treatment in a high pressure oxygen furnace. Measurements are presented of the low temperature heat capacity of the insulating crystal in zero field between 1K and 3K, and of the superconducting crystal in fields of 0, 2 and 4 Tesla applied parallel to the ab plane between 0.2K and 3K. A linear heat capacity contribution is observed for the crystal in both the insulating and superconducting states. This linear heat capacity contribution is larger in the superconducting state and is insensitive to the applied magnetic field.     

Quantum chemical investigations of charge transfer interactions in relation to the electronic theory of cancer. II

The results of ab initio “supermolecule” calculations of the charge transfer between formamide and methylglyoxal, ethylglyoxal, and dimethylglyoxal are compared for several different relative conformations of the constituent molecules. The charge transfer properties of ethylglyoxal were found to be quite different to those of the other two glyoxals.     

Ab initio calculations of the equilibrium geometry of cis and trans methylglyoxal using the force method

Ab initio calculations of the equilibrium ground-state conformation of trans-methylglyoxal, CH₃COCHO, have been carried out using the gradient method and a 4-3 IG basis set. The results are compared with experiment and with a theoretical geometry computed using an STO-3G basis set, and the more usual stepwise optimization of the parameters. The molecular orbital energies, dipole moment and ionization energy are calulated. Calculations are also carried out on the cis-isomer and the barrier to cis-trans isomerization is obtained.