The compounds RMn2O5 have been informed to be magnetoelectric. Substitution of one Mn by Fe or Cr has been informed for RFeMnO5 (R= Y, Tb, Dy, Ho, Er and Yb) and RCrMnO5 (R= Y and Dy). Here we propose the determination of the crystal and magnetic structures at RT and 4K in D2B and its evolution with temperature in D20 of some new compounds belonging to the family RCrMnO5 synthesized by us by the first time at high O2 pressure at temperatures in the range 900-1000 ˚C, where R= Nd, Tb, Ho and Er. We expect to determine the influence of the Cr and Mn occupations on the octahedral and pyramidal sites on the magnetic structures and also to confirm the presence of R vacancies which were observed by Rietveld analysis of PXRD on these compounds and its influence on the structural and magnetic properties.