The first calculation with DALTON

 

If we have made two input files, one corresponding to DALTON.INP  and one corresponding to the MOLECULE \   input file, we are ready to do our first calculation. Examples of input files can be found in the dalton/test directory in order to give you a head-on start with DALTON .

Calculations with DALTON is most conveniently done using the supplied shell-script  dalton. Thus, to run a calculation of (first hyperpolarizability)  with input available as beta.dal on the HCl molecule, with molecule input available as hcl.mol. In order to run this calculation you would type

> dalton beta hcl

assuming dalton is available in your path. When the job is finished, the output is copied back as beta_hcl.out. In case that the dalton- and molecule-input has the same name (e.g. dalton test1 test1), the output will be named test1.out.

There are several options to this script, which can be viewed by typing dalton -h or just dalton. These options include:

-a
Copy various auxillary files  from the home directory to the scratch directory before the calculation starts. This is needed in case of restarts of intrisic reaction coordinate, direct dynamics, Raman Optical Activity, or general numerical differentiation, where information stored in the files DALTON.IRC, DALTON.TRJ, and DALTON.WLK respectively is needed.
-A
Copy various auxillary files  from the scratch directory to the home directory after the calculation has completed. These auxillary files contains extra information that may become useful for certain kinds of calculations. All these auxillary files are described below.
-b directory
Give an alternative directory where the program should look for basis sets . Needed in case you want to use local modifications of a given basis. Note that the directory must end with a /.
-d
Removes the contents of the scratch directory before a calculation starts in order to avoid inconsistencies between files.
-D
Do not remove the content of the scratch directory. By default the scratch directory will be deleted. However, in order to do a restart you will need to keep all files in this directory, and you then need to add the -D option when submitting the job.
-e ext
Change the extension to the output file from .out to .ext.
-f
Copy the fort.21  file from your home directory to the scratch directory before the calculation starts. This is needed in order to be able to do a restart in the wave function optimization.
-F
Copy the fort.21  file from the scratch directory to your home directory after the calculation has finished. This is needed if you want to (re)start  from the wave function created in this run.
-m mem
Change the default size of the scratch memory  space to mem words.
-n nodes
Number of nodes to be used in a parallel MPI calculation controlled by running mpirun.
-t tmpdir
Change the TMPDIR (the scratch disc area) to tmpdir from the default scratch directory determined at install-time.

In most cases, the DALTON.OUT file will contain all the information needed about a given calculations. However, in certain cases, additional information may be wanted, and this is contained in various sets of auxillary files. Their contents is described briefly here. We note that in order for these files to be copied back to your job directory the flag -a must be supplied to the dalton run script.

DALTON.BAS

Contains a dump of a complete molecule input file obtainable by the keyword .MOLPRI  . This file take maximum advantage of formatted input, yet differences may occur compared to the basis sets obtained from the basis set library due to the restricted number of digits available in the standard-form output.

DALTON.MOL

Contains the information needed by the MOLPLT-program for visualizing the molecular geometry. The MOLPLT-program is distributed with the GAMESS-US program package .

DALTON.NCA

Contains the information needed by the MOLPLT-program for visualizing normal coordinates .

DALTON.ORB

Contains information about basis set and MO-coefficients so that MO density plots may be generated using the PLTORB program that comes with the GAMESS-US distribution. Currently not supported .

DALTON.IRC

Contains information obtained from an Intrinsic reaction Coordinate (IRC) calculation, as described in Sec.   .

DALTON.WLK

Contains information from the walk-procedure, and is needed when restarting a walk (e.g. a numerical differentiation).

DALTON.TRJ

Contains information from a direct dynamics calculation as described in Sec.  .

DALTON.CM

An output file that contains the most essential information needed for calculation of shielding and magnetizability polarizabilities. Most easily used together with the analyzing program ODCPRG.f supplied in the tool-directory   .

DALTON.HES

If the keyword .HESPUN   has been specified in the *VIBANA   input module, the molecular Hessian  will be written to this file in a standard format, which may be used as a start Hessian in an first-order  geometry optimization, or as input to a ROA or VCD      analysis with different basis sets/level of correlation for the intensity operators and the force field. See also the FChk2HES.f program in the tool-directory.

DALTON.MOPUN

Contains the molecular-orbital coefficients printed in a standard format allowing the transfer of molecular orbitals coefficients from one computer to another.