<div dir="ltr">Hi everyone: I am trying MP2 for a condensed system (21^3 AA cell with 1000 C H O atoms) with xyz periodic conditions, on a cluster of 10 nodes with the memory of 128GB/node and 24 processors/node. I set the HF and MP2 section as: &HF FRACTION 1.0 &SCREENING EPS_SCHWARZ 5.0E-10 &END &INTERACTION_POTENTIAL POTENTIAL_TYPE TRUNCATED CUTOFF_RADIUS 10.0 T_C_G_DATA ../t_c_g.dat &END &MEMORY MAX_MEMORY 750 &END &END &WF_CORRELATION METHOD RI_MP2_GPW MEMORY 1000 # the memory NUMBER_PROC 10 &WFC_GPW CUTOFF 300 REL_CUTOFF 50 EPS_FILTER 1.0E-12 EPS_GRID 1.0E-8 &END &END But the calculation always stopped at the output of: HFX_MEM_INFO| Est. max. program size before HFX [MB's]: 5xx MB with an Error Messages of Out of Memory. For our system, the Memory available for every node is 128G/24=5.3 GB. In this way, it seems the setting of HF : 750Mb, and 1GB for MP2 are reasonable. Is this right? How the memory consumption of MP2 is determined for the MPI implementation? Is NUMBER_PROC 10 relevent ? I set it as the total number of nodes is 10. Thanks very much for any information. Bin Gu </div>