Abstract
We study within a mean field theory the superconducting phase of kappa-(BEDT-TTF)(2)X organic superconductors. These two dimensional compounds can be described by a two-band model which depends on two parameters t(1) and t(2). We have considered that the superconducting state is induced by spin fluctuations and the gap symmetry is of d, type. We have then determined the dependence of the energy gap on the ratio t(1)/t(2), which gives us the behavior of the superconducting transition temperature. We show that t(1)/t(2) may mimics either a chemical pressure or a hydrostatic one. Our results are in a good agreement with recent experiments suggesting a d(xy) wave symmetry. (C) 2004 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.