The input is divided into modules , which in turn are further divided into submodules . The modules contain the input to the different sections that constitute the DALTON program package. There exists four such sections corresponding to respectively the integral evaluation , the choice of wave function, the choice of static properties and finally the choice of dynamic properties . For each of these sections there exists a module with a name started by two stars, that is:
In addition there is a module controlling the DALTON program, which has the input card **DALTON . All input modules will be described in detail in separate chapters in the Reference Manual.
For geometry optimizations , different options may often be wanted for different stages of the geometry optimization, and there exists three different ABACUS input modules for geometry optimizations: **START , **PROPERTIES , **FINAL . **START gives input for the initial point, **PROPERTIES gives input options during the optimization of the molecular geometry, and **FINAL gives input options for the analysis that is to be done at the optimized geometry. In this way one may start a calculation at an experimental geometry, evaluating a set of molecular properties of interest, do an ordinary geometry optimization without any properties evaluated during the geometry optimization, and then recalculate the same set of molecular properties (or others) at the optimized geometry in one single run. We note that if one only does a single point calculation, input options to ABACUS is to be given in the **PROPERTIES input module.
The input file must end with the keyword *END OF .
In a given module, several submodules may be specified, which determine the performance in various parts of the calculation. The different input cards available in the different submodules is started with a dot, i.e. an input option should be typed as .IMAGE . For most calculations the default settings may be used. The authors have, however, always apted for the largest degree of freedom, giving the user good opportunities for tailoring an input to suit the needs of a given calculation.
Even though we at times write large, self-explanatory keywords in this
manual, only the first seven characters (including the . or
*) are significant and will be
treated by the program. At any
place in the input, comments may be added using
# or !
in the first position of the command line.
A general input structure for DALTON will look like
**GENERAL ... **INTEGRALS ... **WAVE FUNCTIONS ... *CONFIGURATION INPUT ... **START ... **PROPERTIES ... **FINAL ... **RESPONSE *CUBIC ... *END OF INPUT
Several submodules can of course be added in each of the above modules. We also note that if RESPONSE is requested in a geometry optimization, the evaluation of the response functions will only be done at the optimized geometry.
Examples of input files can be found in the various chapters describing the calculation of different molecular properties, and these chapters will probably be sufficient for most calculations done with DALTON . However, all possible keywords are described in detail in separate chapters in the Reference Manual.