Help on EMSL Basis Set Order Form

The Environmental Molecular Sciences Laboratory (EMSL) Basis Set Order Form allows you to extract Gaussian basis sets, and any related effective core potentials, from the Molecular Science Research Center's Basis Set Library. A user may request the basis set be formatted appropriately for a wide variety of popular electronic structure packages. In addition to the exponents and contraction coefficient which define the basis set, the user can obtain descriptive data which includes the overall philosophy behind the basis, literature citations, the angular momentum composition of the basis and many other pieces of information.

The data contained in the EMSL Basis Set Library has been collected by Dr. David Feller. Many, but not all, of the sets have been verified to reproduce energies in the chemistry literature. However, the combination of a large number of basis sets along with multiple output formats makes the job of insuring the correctness of the information quite difficult. Users are advised to check the correctness of the basis sets whenever possible. The size of the data base and the number of supported output formats will continue to grow. If you have requests for specific basis sets that you would like to see in this utility, or if you don't find the format of your favorite code among those currently supported, please send requests to mscf@pnl.gov. The staff of the EMSL, particularly Drs. D. Woon, K. Peterson and T. H. Dunning, Jr., are thanked for their significant contributions to this project.

We ask that you register when you order so that we can track interest in this service and contact you if any errors are found in the data.

Selecting Basis Sets

In order to extract a basis set you must first click on a basis set name in the scrolling list to select it. Currently only one basis set may be selected per request.

Specifying Elements

After the basis set has been selected you should type in a list of elements, separated by spaces, for every atom you want. This field is NOT case sensitive. For example: "C Ne Rb" is the same as "c ne rb". If you type in an invalid symbol, you will get an error message after you submit the request.

Since Mosaic forms aren't interactive we cannot catch errors such as invalid symbols and unsupported elements until you submit the request.

Output Options

Optimize General Contraction

 If this option is checked, general contractions will be reformatted to work more efficiently with codes that support only segmented contractions.

Effective Core Potentials

 If this option is checked and the selected basis set is associated with an Effective Core Potential, the ECP will also be returned.

Show Supported Elements

 If this option is checked, a list of elements supported by the selected basis set will be provided. The list will be provided even if no elements have been entered in the Elements text field.

Show Supporting Basis Sets

 If this option is checked, a list of basis sets that support the elements indicated in the Elements text area will be provided. If no elements are supplied an empty list of basis sets is returned.

Code

Click to select the appropriate format. We have insured that the formats are correct for the latest versions of the programs which are available at the EMSL. If the version you are running differs considerably from these, it may be necessary for you to manually tweak the basis sets.

Results from Submit Action

 When you submit the order, the requested data set will be displayed. You will also be provided with a link to descriptive textual data including references about the selected basis set. If there is a graphical image available, there will be a link to access it as well. The graphical images are experimental so there are very few of them at this time.

The software that returns the data set will return warning and/or error messages to you if the options you specified are not compatible.

Reset

This option sets all user interface controls to their original state. The entry for Elements is cleared, the code type is reset to GAMESS, Optimize General Contractions is turned on and ECP Potentials is turned off.

Email Address

 We request that you supply your email address so that you can be notified if an error is found in the data.