Perform Basic Operations

Use the Basis Set Tool to select basis sets for chemical systems and save them for use with Ecce calculations or external programs.

Select Basis Sets for a Calculation

1. To use the Basis Set Tool in the context of a Calculation:
   
   • In the Calculation Manager - Select a calculation. From the Tools menu, choose Basis Set Tool.
   • In the Calculation Editor - Click on the Basis Set button.
   • Use the middle mouse button to drag a calculation from the Calculation Manager to the drop site of the Basis Set Tool.
   
   
2. Optional: In the Periodic Table, click on elements of interest.
   
   Then only basis sets that support the selected elements are listed in the basis set list (to the left of the Periodic Table).
   
   
3. Use the tabs along the top and side of the basis set list to view different subsets of the Gaussian Basis Set Library.
   
   
4. Double-click on basis sets in the list to select them.
   -OR-
   Select a basis set on the list and click on the "Add to Table" button.
   
   Each selected basis set is displayed in the tabbed table below the basis set list.
   
   
5. In the tabbed table, choose to apply basis sets to individual elements or to all atoms in the current chemical system.
   
   
6. From the Molecular Basis menu, choose Save (or click on the "Save Work" icon ).
   
   The selected basis sets are saved as part of the calculation.

Browse Basis Sets for an Arbitrary System

To browse basis sets for a chemical system outside the context of a specific calculation:

1. From the Browse Options menu, mark the Browse Mode option.
   
   The Chemical Formula field above the Periodic Table then becomes active.
   
   
2. Type a chemical formula in the Chemical Formula field, or import a chemical system.

   You can then browse and select basis sets as you would for a calculation, but you cannot save any selected basis sets to a specific calculation.
   
   

3. In the panel of options near the lower right corner of the Basis Set Tool, mark options that will affect the selected basis functions: the computational code format, polarization components, and general contractions optimization.
   
   
4. To save your work: either save the selected basis sets as a user defined combination, or export the basis sets for use outside Ecce.

Create a Private Basis Set Library

Export Basis Sets for Use Outside Ecce

To export the current selection of basis sets to an ASCII file for use by another program:

1. Select the appropriate computational code and other options in the options panel.

2. From the Molecular Basis menu, choose Save to File.

   The resulting file dialog window enables you to name the exported file and specify its location.

Import a Chemical System (Structure)

1. From the Browse Options menu, choose Import Structure.
   
   This opens the Import Dialog window.

   Picture...

   Import Dialog Window

   
   
2. From the Format menu, choose the desired format.
   
   
3. Optional: At the end of the Filter string, type a filter for limiting the files that will be displayed in the Files list. Then press Enter (or click on the Filter button)
   
   
4. In the Directories list, click on the appropriate source directory.
   
   
5. In the Files list, click on the file to import.
   
   The selected file is listed in the Selection box.
   
   
6. Click on the Import button.
   
   If the format is incorrect, you will see an error message.