Creating a data file

PGOPHER data files (.pgo files) contain the rotational constants and other settings required to perform a simulation. An empty file can be created from the File menu, but it is normally easiest to modify an existing .pgo file. For linear molecules some of the basic ideas are discussed in Making a Linear Molecule Data File  and some more complicated examples are linked below:

O2 microwave spectrum
CFBr electronic spectrum
C2 Swan band

Note: All quantum numbers (spin, J, K...) are input and displayed at double their actual values to allow for half integral values.

Modifications to the file (either modifications to individual settings and parameters, or more major changes such as addition or deletion of species, molecules, manifolds, states, perturbations or transition moments) can then be effected in the constants window, using the tree view. The data file contains a hierarchy of objects, to represent the molecules and states involved in the transition; this works rather like a nested directory structure containing files except that each level can only contain certain types of object. (The top level object must be Species, for example.) Data files can also be merged to combine spectra.

The .pgo files are in XML format, and can be edited with an ordinary text editor if required. (If you load a .pgo file into a web browser it will normally show the XML nicely laid out and colour coded.)

To simulate a spectrum click on the simulate Simulate button in the main window.