NEUTRON-DIFFRACTION AND MAGNETIZATION STUDIES OF SR2RUO4 BELOW 2 K

High resolution neutron powder diffraction and magnetisation measureme nts have been carried out on the superconductor, Sr2RuO4. The powder d iffraction data has been refined at high and low temperatures to obtai n lattice parameters below the superconducting transition temperature( 1.15 K) and at elevated temperatures where Sr2RuO4 is used as a substr ate for the deposition of YBa2Cu3O7 thin films. No evidence has been f ound for any lattice distortions between 100 mK and 2 K in Sr2RuO4. Ma gnetisation measurements between 0.7 K and room temperature has indica ted the onset of superconductivity at 1.15 K.