How to improve the speed of dft optimization of Cu in ecp model

Click here for full thread

Clicked A Few Times

11:50:40 PM PDT - Tue, Jun 20th 2017
I want to optimize a structure including 56 Cu in ecp model.But I found that it run too slowly.Here is my all input file: memory 10000 mb echo title "M06-L/LanL2DZ ECP Cu2 " scratch_dir ./scratch permanent_dir ./perm start cu2 geometry Cu 0.0000000000000008881784 2.9516020000000000000000 -4.1741970000000000000000 Cu 2.5561630000000000000000 2.9516020000000000000000 -4.1741970000000000000000 Cu 1.2780810000000000000000 5.1653040000000000000000 -4.1741970000000000000000 Cu 5.1123250000000000000000 2.9516020000000000000000 -4.1741970000000000000000 Cu 3.8342440000000000000000 5.1653040000000000000000 -4.1741970000000000000000 Cu 2.5561630000000000000000 7.3790060000000000000000 -4.1741970000000000000000 Cu 6.3904070000000000000000 5.1653040000000000000000 -4.1741970000000000000000 Cu 5.1123250000000000000000 7.3790060000000000000000 -4.1741970000000000000000 Cu 3.8342440000000000000000 9.5927080000000000000000 -4.1741970000000000000000 Cu -0.0000000000000004440892 1.4758010000000000000000 -2.0871000000000000000000 Cu -1.2780810000000000000000 3.6895030000000000000000 -2.0871000000000000000000 Cu 2.5561630000000000000000 1.4758010000000000000000 -2.0871000000000000000000 Cu 1.2780810000000000000000 3.6895030000000000000000 -2.0871000000000000000000 Cu 0.0000000000000004440892 5.9032050000000000000000 -2.0871000000000000000000 Cu 5.1123250000000000000000 1.4758010000000000000000 -2.0871000000000000000000 Cu 3.8342440000000000000000 3.6895030000000000000000 -2.0871000000000000000000 Cu 2.5561630000000000000000 5.9032050000000000000000 -2.0871000000000000000000 Cu 1.2780810000000000000000 8.1169070000000000000000 -2.0871000000000000000000 Cu 6.3904070000000000000000 3.6895030000000000000000 -2.0871000000000000000000 Cu 5.1123250000000000000000 5.9032050000000000000000 -2.0871000000000000000000 Cu 3.8342440000000000000000 8.1169070000000000000000 -2.0871000000000000000000 Cu 2.5561630000000000000000 10.3306100000000000000000 -2.0871000000000000000000 Cu 7.6684880000000000000000 5.9032050000000000000000 -2.0871000000000000000000 Cu 6.3904070000000000000000 8.1169070000000000000000 -2.0871000000000000000000 Cu 5.1123250000000000000000 10.3306100000000000000000 -2.0871000000000000000000 Cu -0.0000000000000004440892 0.0000000000000000000000 0.0000000000000000000000 Cu -1.2780810000000000000000 2.2137020000000000000000 0.0000000000000000000000 Cu -2.5561630000000000000000 4.4274040000000000000000 0.0000000000000000000000 Cu 2.5561630000000000000000 0.0000000000000000000000 0.0000000000000000000000 Cu 1.2780810000000000000000 2.2137020000000000000000 -6.2612960000000000000000 Cu 1.2780810000000000000000 2.2137020000000000000000 0.0000000000000000000000 Cu 0.0000000000000004440892 4.4274040000000000000000 0.0000000000000000000000 Cu -1.2780810000000000000000 6.6411060000000000000000 0.0000000000000000000000 Cu 5.1123250000000000000000 0.0000000000000000000000 0.0000000000000000000000 Cu 3.8342440000000000000000 2.2137020000000000000000 -6.2612960000000000000000 Cu 3.8342440000000000000000 2.2137020000000000000000 0.0000000000000000000000 Cu 2.5561630000000000000000 4.4274040000000000000000 -6.2612960000000000000000 Cu 2.5561630000000000000000 4.4274040000000000000000 0.0000000000000000000000 Cu 1.2780810000000000000000 6.6411060000000000000000 0.0000000000000000000000 Cu 0.0000000000000013322680 8.8548070000000000000000 0.0000000000000000000000 Cu 6.3904070000000000000000 2.2137020000000000000000 0.0000000000000000000000 Cu 5.1123250000000000000000 4.4274040000000000000000 -6.2612960000000000000000 Cu 5.1123250000000000000000 4.4274040000000000000000 0.0000000000000000000000 Cu 3.8342440000000000000000 6.6411060000000000000000 -6.2612960000000000000000 Cu 3.8342440000000000000000 6.6411060000000000000000 0.0000000000000000000000 Cu 2.5561630000000000000000 8.8548070000000000000000 0.0000000000000000000000 Cu 1.2780810000000000000000 11.0685100000000000000000 0.0000000000000000000000 Cu 7.6684880000000000000000 4.4274040000000000000000 0.0000000000000000000000 Cu 6.3904070000000000000000 6.6411060000000000000000 -6.2612960000000000000000 Cu 6.3904070000000000000000 6.6411060000000000000000 0.0000000000000000000000 Cu 5.1123250000000000000000 8.8548070000000000000000 -6.2612960000000000000000 Cu 5.1123250000000000000000 8.8548070000000000000000 0.0000000000000000000000 Cu 3.8342440000000000000000 11.0685100000000000000000 0.0000000000000000000000 Cu 8.9465700000000000000000 6.6411060000000000000000 0.0000000000000000000000 Cu 7.6684880000000000000000 8.8548070000000000000000 0.0000000000000000000000 Cu 6.3904070000000000000000 11.0685100000000000000000 0.0000000000000000000000 end basis Cu library "LANL2DZ ECP" end ecp Cu library "LANL2DZ ECP" end dft print "final vectors analysis" xc m06-L mult 1 grid coarse iterations 2000 convergence energy 1e-4 convergence density 1e-4 end driver maxiter 2000 xyz rs end task dft optimize How to improve the running speed?