In this experiment we propose to perform neutron diffraction measurements on lithium intercalation compounds,Li2xMn1-xPS3,at room temperature,40ºC,75 ºC,150ºC and under vacuum (pressure of about 10-4torr).The samples are crystalline films casted on aluminum substrates.We would like to obtain information about the Li+ atomic environment (where the solvated Li+ ions are) and how the Li ions behave when temperature changes and/or when films are under vacuum condition.These informations are essential to understand the role of the Li+ ions in the dielectric response of these films. Since Li is a poor x-ray scatterer little informations are known about the detailed structural features of the Li2xMn1-xPS3 films:only the basal spacing is reported in the literature at different temperatures during a dehydration/rehydration cycle.