Suppression of superconductivity in a molecular charge transfer salt by changing guest molecule: β″-(BEDT-TTF)[(H O)Fe(CO)](CH CN)(CHN)

SQUID magnetometry and transport measurements combined with crystal structure refinement have been used to examine the variation in superconducting properties (T and Meissner fraction) in the molecular superconductor β″-(BEDT-TTF)[(HO)Fe(CO )]·CHCN on replacing the CHCN guest molecule with pyridine (CH N). Up to approximately 65% pyridine substitution there is only a small decrease in T and Meissner fraction but above that the superconductivity is suppressed. © The Royal Society of Chemistry 2007.