The organic-inorganic perovskites with chemical formula CH3NH3PbB(Br,Cl,I)3 have been implicated as being efficient photovoltaic materials. Theoretical calculations and experiments performed by our group have indicated a strong coupling between molecular dynamics and electronic band structure and also the host Pb -based framework. This proposal aims to obtain a full three dimensional map of the quasielastic scattering from the molecular motions at temperatures below and above the structural transition. This will be used to obtain information on how the molecular motions are correlated in real space and related to ongoing work on powder samples. The entire proposal requests 5 days of time (2.5 days at both temperatures).