We have accumulated expertise in treating the diffraction data collected on twinned manganites as if it had collected on a single crystal. We obtained in the past good single crystal structural data at intermediate temperature (TN<T<TCO) on PrCaMnO3 charge ordered manganites, but we realize that we still miss one data collection at low temperature to get a complete view on the physics/ground state of these complex materials. The purpose of the experiment is to fill this gap.