Input text file keywords#
Keywords for the various input sections in the program input file can be listed by means of the print_keyword() class method. Examples are given below.
Tasks#
The different taks below are presented in the same order followed for the Properties description.
Task  | 
Description  | 
|---|---|
Perform a Restricted closed-shell calculation (HF or DFT)  | 
|
Perform a Restricted open-shell calculation (HF or DFT)  | 
|
Perform a Unrestricted open-shell calculation (HF or DFT)  | 
|
Perform a Restricted closed-shell MP2 calculation  | 
|
Perform a Restricted open-shell MP2 calculation  | 
|
Perform a Unrestricted open-shell MP2 calculation  | 
|
Calculate the ESP charges  | 
|
Calculate the RESP charges  | 
|
Calculate the LoProp charges and polarizabilities  | 
|
Optimize the geometry in the ground and excited state  | 
|
Calculate response properies with TD-DFT and CPP, such as UV/vis or ECD  | 
|
Use the exciton coupling model to calculate absorption and circular dichroism  | 
|
Calculate IR, Raman and resonance Raman spectra  | 
Molecule#
mol = vlx.Molecule()
mol.print_keywords()
                ==========================================================================================                
                  @molecule                                                                                               
                ------------------------------------------------------------------------------------------                
                  charge        integer     net charge                                                                    
                  multiplicity  integer     spin multiplicity                                                             
                  units         string      unit of coordinates, default is Angstrom                                      
                  xyz           multi-line  atom and Cartesian coordinates                                                
                  xyzfile       string      XYZ file name (conflicts with units/xyz)                                      
                ==========================================================================================                
SCF optimization#
Here are printed the keywords for the ScfRestrictedDriver(), the same can be done for the ScfRestrictedOpenDriver() and ScfUnrestrictedDriver()
scf_drv = vlx.ScfRestrictedDriver()
scf_drv.print_keywords()
                ==========================================================================================                
                  @scf                                                                                                    
                ------------------------------------------------------------------------------------------                
                  acc_type                  string      type of SCF convergence accelerator                               
                  max_iter                  integer     maximum number of SCF iterations                                  
                  max_err_vecs              integer     maximum number of DIIS error vectors                              
                  pfon                      boolean     use pFON to accelerate convergence                                
                  pfon_temperature          float       pFON temperature                                                  
                  pfon_delta_temperature    float       pFON delta temperature                                            
                  pfon_nocc                 integer     number of occupied orbitals used in pFON                          
                  pfon_nvir                 integer     number of virtual orbitals used in pFON                           
                  level_shifting            float       level shifting parameter                                          
                  level_shifting_delta      float       level shifting delta                                              
                  conv_thresh               float       SCF convergence threshold                                         
                  eri_thresh                float       ERI screening threshold                                           
                  ovl_thresh                float       AO linear dependency threshold                                    
                  restart                   boolean     restart from checkpoint file                                      
                  filename                  string      base name of output files                                         
                  checkpoint_file           string      name of checkpoint file                                           
                  timing                    boolean     print timing information                                          
                  profiling                 boolean     print profiling information                                       
                  memory_profiling          boolean     print memory usage                                                
                  memory_tracing            boolean     trace memory allocation                                           
                  print_level               integer     verbosity of output (1-3)                                         
                  guess_unpaired_electrons  string      unpaired electrons for initila guess                              
                  point_charges             string      potential file for point charges                                  
                  qm_vdw_params             string      vdw parameter file for QM atoms                                   
                ==========================================================================================                
                  @method settings                                                                                        
                ------------------------------------------------------------------------------------------                
                  ri_coulomb                boolean     use RI-J approximation                                            
                  ri_jk                     boolean     use RI-JK approximation                                           
                  ri_auxiliary_basis        string      RI auxiliary basis set                                            
                  dispersion                boolean     use D4 dispersion correction                                      
                  xcfun                     string      exchange-correlation functional                                   
                  grid_level                integer     accuracy level of DFT grid (1-8)                                  
                  potfile                   string      potential file for polarizable embedding                          
                  solvation_model           string      solvation model                                                   
                  cpcm_grid_per_sphere      sequence    number of C-PCM grid points per sphere                            
                  cpcm_cg_thresh            float       threshold for solving C-PCM charges                               
                  cpcm_epsilon              float       dielectric constant of solvent (C-PCM)                            
                  cpcm_x                    float       parameter for scaling function (C-PCM)                            
                  cpcm_custom_vdw_radii     sequence    custom vdw radii for C-PCM                                        
                  electric_field            sequence    static electric field                                             
                ==========================================================================================                
UV/vis absorption spectrum#
prop = vlx.Absorption()
prop.init_driver()
prop.print_keywords()
                ==========================================================================================                
                  @response                                                                                               
                ------------------------------------------------------------------------------------------                
                  eri_thresh             float       ERI screening threshold                                              
                  batch_size             integer     batch size for Fock build                                            
                  conv_thresh            float       convergence threshold                                                
                  max_iter               integer     maximum number of iterations                                         
                  norm_thresh            float       norm threshold for adding vector                                     
                  lindep_thresh          float       threshold for linear dependence                                      
                  serial_ratio           float       serial ratio as in Amdahl's law                                      
                  use_subcomms           boolean     use subcommunicators for Fock build                                  
                  restart                boolean     restart from checkpoint file                                         
                  filename               string      base name of output files                                            
                  checkpoint_file        string      name of checkpoint file                                              
                  force_checkpoint       boolean     flag for writing checkpoint every iteration                          
                  save_solutions         boolean     save solutions to file                                               
                  timing                 boolean     print timing information                                             
                  profiling              boolean     print profiling information                                          
                  memory_profiling       boolean     print memory usage                                                   
                  memory_tracing         boolean     trace memory allocation                                              
                  print_level            integer     verbosity of output (1-3)                                            
                  non_equilibrium_solv   boolean     toggle use of non-equilibrium solvation for response                 
                  nstates                integer     number of excited states                                             
                  core_excitation        boolean     compute core-excited states                                          
                  num_core_orbitals      integer     number of involved core-orbitals                                     
                  nto                    boolean     analyze natural transition orbitals                                  
                  nto_pairs              integer     number of NTO pairs in NTO analysis                                  
                  nto_cubes              boolean     write NTO cube files                                                 
                  detach_attach          boolean     analyze detachment/attachment density                                
                  detach_attach_cubes    boolean     write detachment/attachment density cube files                       
                  esa                    boolean     compute excited state absorption                                     
                  esa_from_state         integer     the state to excite from (e.g. 1 for S1)                             
                  cube_origin            sequence    origin of cubic grid points                                          
                  cube_stepsize          sequence    step size of cubic grid points                                       
                  cube_points            sequence    number of cubic grid points                                          
                  tamm_dancoff           boolean     use Tamm-Dancoff approximation                                       
                ==========================================================================================                
                  @method settings                                                                                        
                ------------------------------------------------------------------------------------------                
                  ri_coulomb             boolean     use RI-J approximation                                               
                  ri_auxiliary_basis     string      RI-J auxiliary basis set                                             
                  xcfun                  string      exchange-correlation functional                                      
                  grid_level             integer     accuracy level of DFT grid                                           
                  potfile                string      potential file for polarizable embedding                             
                  electric_field         sequence    static electric field                                                
                  solvation_model        string      solvation model                                                      
                  cpcm_grid_per_sphere   sequence    number of C-PCM grid points per sphere                               
                  cpcm_cg_thresh         float       threshold for solving C-PCM charges                                  
                  cpcm_epsilon           float       dielectric constant of solvent (C-PCM)                               
                  cpcm_optical_epsilon   float       optical dielectric constant of solvent (C-PCM)                       
                  cpcm_x                 float       parameter for scaling function (C-PCM)                               
                  cpcm_custom_vdw_radii  sequence    custom vdw radii for C-PCM                                           
                ==========================================================================================                
Complex response solver#
cpp_solver = vlx.ComplexResponse()
cpp_solver.print_keywords()
                ==========================================================================================                
                  @response                                                                                               
                ------------------------------------------------------------------------------------------                
                  eri_thresh             float       ERI screening threshold                                              
                  batch_size             integer     batch size for Fock build                                            
                  conv_thresh            float       convergence threshold                                                
                  max_iter               integer     maximum number of iterations                                         
                  norm_thresh            float       norm threshold for adding vector                                     
                  lindep_thresh          float       threshold for linear dependence                                      
                  serial_ratio           float       serial ratio as in Amdahl's law                                      
                  use_subcomms           boolean     use subcommunicators for Fock build                                  
                  restart                boolean     restart from checkpoint file                                         
                  filename               string      base name of output files                                            
                  checkpoint_file        string      name of checkpoint file                                              
                  force_checkpoint       boolean     flag for writing checkpoint every iteration                          
                  save_solutions         boolean     save solutions to file                                               
                  timing                 boolean     print timing information                                             
                  profiling              boolean     print profiling information                                          
                  memory_profiling       boolean     print memory usage                                                   
                  memory_tracing         boolean     trace memory allocation                                              
                  print_level            integer     verbosity of output (1-3)                                            
                  non_equilibrium_solv   boolean     toggle use of non-equilibrium solvation for response                 
                  a_operator             string      A operator                                                           
                  a_components           string      Cartesian components of A operator                                   
                  b_operator             string      B operator                                                           
                  b_components           string      Cartesian components of B operator                                   
                  frequencies            sequence    frequencies                                                          
                  damping                float       damping parameter                                                    
                ==========================================================================================                
                  @method settings                                                                                        
                ------------------------------------------------------------------------------------------                
                  ri_coulomb             boolean     use RI-J approximation                                               
                  ri_auxiliary_basis     string      RI-J auxiliary basis set                                             
                  xcfun                  string      exchange-correlation functional                                      
                  grid_level             integer     accuracy level of DFT grid                                           
                  potfile                string      potential file for polarizable embedding                             
                  electric_field         sequence    static electric field                                                
                  solvation_model        string      solvation model                                                      
                  cpcm_grid_per_sphere   sequence    number of C-PCM grid points per sphere                               
                  cpcm_cg_thresh         float       threshold for solving C-PCM charges                                  
                  cpcm_epsilon           float       dielectric constant of solvent (C-PCM)                               
                  cpcm_optical_epsilon   float       optical dielectric constant of solvent (C-PCM)                       
                  cpcm_x                 float       parameter for scaling function (C-PCM)                               
                  cpcm_custom_vdw_radii  sequence    custom vdw radii for C-PCM                                           
                ==========================================================================================                
Optimization driver#
opt_drv = vlx.OptimizationDriver(scf_drv)
opt_drv.print_keywords()
                ==========================================================================================                
                  @optimize                                                                                               
                ------------------------------------------------------------------------------------------                
                  coordsys        string      coordinate system                                                           
                  constraints     multi-line  constraints                                                                 
                  check_interval  integer     interval for checking coordinate system                                     
                  trust           float       trust radius to begin with                                                  
                  tmax            float       maximum value of trust radius                                               
                  max_iter        integer     maximum number of optimization steps                                        
                  transition      boolean     transition state search                                                     
                  irc             boolean     flag for intrinsic reaction coordinate                                      
                  hessian         string      hessian flag                                                                
                  ref_xyz         string      reference geometry                                                          
                  keep_files      boolean     flag to keep output files                                                   
                  conv_maxiter    boolean     consider converged if max_iter is reached                                   
                  conv_energy     float                                                                                   
                  conv_grms       float                                                                                   
                  conv_gmax       float                                                                                   
                  conv_drms       float                                                                                   
                  conv_dmax       float                                                                                   
                ==========================================================================================