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A Tutorial for Columbus Usage of Symmetry and Parallel Calculations

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A Tutorial for Columbus Usage of Symmetry and Parallel Calculations A TUTORIAL FOR COLUMBUS USAGE OF SYMMETRY AND PARALLEL CALCULATIONS Felix Plasser Institute for Theoretical Chemistry – University of Vienna Vienna, 2011 Table of contents Table of contents .................................................................................................................... 2 1. Before starting ................................................................................................................. 3 1.1 Introduction .............................................................................................................. 3 1.2 Notation .................................................................................................................... 3 2. MCSCF single point calculation with symmetry ............................................................ 4 2.1 Orbital occupation and DRT tables .......................................................................... 4 2.2 Geometry file ........................................................................................................... 5 2.3 COLINP integral input .............................................................................................. 5 2.4 COLINP step: SCF input ............................................................................................ 6 2.5 COLINP step: MCSCF input ..................................................................................... 7 2.6 Running a MCSCF single point job ......................................................................... 8 2.7 Checking the results ................................................................................................. 9 3. Parallel MR-CISD single point calculation ................................................................... 10 3.1 Basic input ............................................................................................................. 10 3.2 COLINP step: MRCI input ....................................................................................... 10 3.3 Running a parallel MRCI single point job ............................................................. 13 3.4 Checking the results ............................................................................................... 14 3.5 Performance fine tuning ......................................................................................... 14 4. Contact .......................................................................................................................... 15 Appendix: Orbital occupation and DRT tables .................................................................... 16 COLUMBUS tutorial 2 1. Before starting 1.1 Introduction This tutorial will give an introduction into high performance calculations with COLUMBUS . It will be shown how explicit symmetry can be used and how parallel MR-CISD calculations can be set up. The use of symmetry does not only have an advantage in relations to performance, but it also gives more flexibility in the wave function definitions and more immediately meaningful output. The disadvantage is that the input is somewhat more complex and that there are more possibilities for errors. The parallel MR-CISD program pciudg.x is intended for massively parallel calculations up to hundreds of processors. But an efficient load balancing is quite challenging considering the complex nature of MR-CI wave functions. In this tutorial several tools for setting up such a calculation will be presented. 1.2 Notation The same notation as in the standard tutorial will be used. This kind of font indicates what is seen on the screen and the command lines that you should write <ENTER> ! Comments come here Important information related to Columbus but not necessarily connected to the current job comes in boxes like this. COLUMBUS tutorial 3 2. MCSCF single point calculation with symmetry In this section we will prepare a complete input for a single point calculation at MCSCF level with explicit usage of symmetry. The system is the p-dimethylaminobenzonitrile (DMABN), which will be calculated using a complete active space composed by 10 electrons in 9 orbitals [CASSCF(10/9)]. Three states will be included in the state averaging procedure (SA-3) and the cc-pVDZ basis set will be used. The calculation will be performed in the C2v point group). 2.1 Orbital occupation and DRT tables With explicit usage of symmetry, the occupation tables are somewhat more complex. Occupations in each irrep have to obtained from qualitative reasoning, exploratory calculations or by trial and error. 1. Fill out the occupation table. System: DMABN Point Group: C2v N. Electrons: 78 Level: MRCI(6,5)/SA-3-CASSCF(10,9) IRREP a1 b1 b2 a2 SCF DOCC 20 5 12 2 OPSH MCSCF DOCC 20 1 12 1 RAS CAS 0 7 0 2 AUX MRCI FC 8 0 3 0 FV DOCC 12 3 9 1 ACT 0 3 0 2 AUX INT 12 6 9 3 2. Fill out the DRT table. State Multiplicity N. electrons Symmetry 1 1 78 A1 2 1 78 B2 3 1 78 A1 Number of distinct row tables (DRTs): 2 In this case two DRTs are needed, considering that state averaging is performed over two distinct symmetries. COLUMBUS tutorial 4 2.2 Geometry file 3. In the TUTORIAL directory create a subdirectory called DMABN_CAS_SP 4. Move to this directory and create a file called geom.uniq in Columbus format: C 6.0 0.00000000 0.00000000 4.94532492 12.00000000 C 6.0 0.00000000 2.28388802 3.59270636 12.00000000 C 6.0 0.00000000 2.28719145 0.96449136 12.00000000 C 6.0 0.00000000 0.00000000 -0.42775069 12.00000000 C 6.0 0.00000000 0.00000000 7.65220512 12.00000000 C 6.0 0.00000000 2.36428675 -4.37783677 12.00000000 N 7.0 0.00000000 0.00000000 9.88116650 14.00307401 N 7.0 0.00000000 0.00000000 -3.02080924 14.00307401 H 1.0 0.00000000 4.07497903 4.61485947 1.00782504 H 1.0 0.00000000 4.09874337 -0.00853452 1.00782504 H 1.0 0.00000000 1.97923145 -6.40956646 1.00782504 H 1.0 1.68282187 3.51210363 -3.94559387 1.00782504 Only symmetry unique atoms are given here. 2.3 COLINP integral input 5. Run: > $COLUMBUS/colinp -> 1) Integral program input (for argos/dalton/turbocol/molcas) 2) SCF input 3) MCSCF input 4) CI input 5) Set up job control 6) Utilities 7) Exit the input facility 6. Use the prepinp utility Run the preparation program (prepinp)? (y|n) y ! Press <ENTER> after the input 7. Enter information about program, symmetry and geometry file. Input for DALTON (1) or MOLCAS (2): 1 Enter the point group symmetry: c2v ! Only Abelian groups Name of the file containing the cartesian coordinates of the unique atoms (COLUMBUS format): geom.uniq Number of atoms = 12 ! verify that the file was read in correctly Sum formula: H4 C6 N2 8. Enter information about basis sets. Show only basis sets containing the following string: (e.g. 6-31g, cc-pv - leave empty to show all basis sets) cc-pvd COLUMBUS tutorial 5 -- Set basis set -- 1: cc-pvdz (4s,1p)->[2s,1p] 3: aug-cc-pvdz 4: aug'-cc-pvdz (without p function in aug-set) 5: d'-aug-cc-pvdz (without p function in d-set) 6: d-aug-cc-pvdz 15: diffuse functions for cc-pvdz(1s,1p) 0: Other library Select the basis set for atom H: 1 ! cc-pvdz was selected ... Select the basis set for atom N: 1 ... Select the basis set for atom C: 1 ... Until now you've set the following basis sets: H :: cc-pvdz (4s,1p)->[2s,1p] C :: cc-pvdz(9s,4p,1d)->[3s,2p,1d] N :: cc-pvdz(9s,4p,1d)->[3s,2p,1d] Reorder geom file for geometry optimization and orbital print out? (y) y ! per default the geometry should be reordered to put the hydrogens at the back of the file Normal termination of prepinp. See result in inpcol. 9. Perform an automatic input of iargos.x . ... Would you like to do an interactive input? <NO> n ! Select “no” . If you select “yes”, COLINP will ask to enter all information about geometry and basis sets again, atom per atom. In the case of ANO basis sets it is currently necessary to perform the whole interactive iargos.x input. But you may use the file inpcol (as created in the previous step) as a template. 2.4 COLINP step: SCF input 10. Select option 2) SCF input. 1) Integral program input (for argos/dalton/turbocol) -> 2) SCF input 3) MCSCF input 4) CI input 5) Set up job control 6) Exit the input facility ... Do you want a closed shell calculation ? <YES> y Input the no. of doubly occupied orbitals for each irrep, DOCC: 20 5 12 2 ! Insert this according to the orbital occupation table above COLUMBUS tutorial 6 The orbital occupation is: a1 b1 b2 a2 DOCC 20 5 12 2 OPSH 0 0 0 0 Is this correct? <YES> <ENTER> Would you like to change the default program parameters? <NO> <ENTER> Input a title: <Default SCF Title> --> <ENTER> 2.5 COLINP step: MCSCF input 11. Select option 3) MCSCF input 1) Integral program input (for argos/dalton/turbocol/molcas) 2) SCF input -> 3) MCSCF input 4) CI input 5) Set up job control 6) Utilities 7) Exit the input facility MCSCF WAVE FUNCTION DEFINITION ============================== (for an explanation see the COLUMBUS documentation and tutorial) prepare input for no(0),CI(1), MCSCF(2), SA-MCSCF(3) analytical gradient 0 Enter number of DRTS [1-8] 2 ! This information is in the DRT Table number of electrons for DRT #1 (nucl. charge: 78) 78 multiplicity for DRT #1 1 spatial symmetry for DRT #1 1 ! Representation A1 (see Orbital occupation table) excitation level (cas,ras)->aux 0 excitation level ras->(cas,aux) 0 number of electrons for DRT #2 (nucl. charge: 78) 78 multiplicity for DRT #1 1 spatial symmetry for DRT #1 3 ! Representation B2 excitation level (cas,ras)->aux 0 excitation level ras->(cas,aux) 0 number of doubly occupied orbitals per irrep 20 1 12 1 number of CAS orbitals per irrep 0 7 0 2 Apply add.
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