Starting a new project

The basic logical unit, to which the LWW program refers, is a project. It is a collection of files used and generated by the program, stored in one directory, denoted here as the project folder. When a new project is started, a project file (with the “.lww“ extension), which contains all necessary information for opening (loading) the project repeatedly, is created in the project directory, with the name defined by the user. It could be associated with the LWW.exe program, so that double-clicking on it can be used for opening the LWW program, with directly loading the project.

Starting a new project requires the basic information about the rovibrational spectrum and the corresponding rovibrational energies. The following three files are expected to exist in the project directory at the point of staring a new project:

• Peaklist file
• Spectrum file
• Energy file

As the first step of creating a project, the peaklist file, again in a standard Windows dialog for opening a file named Open Peak File Name (required). This file is assumed to be prepared in a .csv (Comma Separated Values) format. With the peaklist file loaded, the LWW program is in the minimum configuration, in which it already works. It can be used for displaying and printing a simulated spectrum, generated from the peaklist.

When the spectrum plot is available, it can be included into the project in the next step using a standard Windows dialog for opening a file named Open Spectrum File Name (optional), in an analogous way like with the peak file. This creates another entry in the project file. In case the spectrum is not available, the project can be started without it, leaving a place for using later a simulated spectrum.

In this configuration, the LWW program can be used for viewing selected sections of the real spectrum and printing it together with the corresponding part of the peaklist. It has the four main windows of the program opened (see Basic windows of the LWW program)

For a full functionality of the LWW program it remains to load the file of rovibrational energies, which is done whenever a new branch is defined in the Add New Branch from Energy File dialog. This loads the file of vibration-rotation energies with their corresponding quantum numbers into the program. From this file the transition wavenumbers of spectral branches are calculated.

At this point the project is ready for using and can be saved.