Dialog Box: Forces List [Control window]
This dialog provides a quick way to change force constant values, or to add or remove them from the list of force constants which are being refined by least-squares.
The force constants are listed 10 at a time - to see others, click on the Last 10 or Next 10 buttons.
To change the specifications for individual force constants, as opposed to the value of the force constant, you must go to the individual dialogs in the Forces menu.
The numbers of the force constants correlate with the "Fcon" numbers in the Output and in the dialog of the Forces menu. The four numbers under Type #s give some information about the specifications for the force constant - if there are more than one specification for a given force constant, only the first is listed here. For bonds, 3-atom angles, tau angles, psi angles and Urey-Bradley X-X bonds, the numbers are the atom types, exactly as in the specifications (dialogs in the Forces menu). For Urey Bradley kappa force constants, the numbers are 1) the number of the U-B polyhedron specification in the list in the Urey-Bradley Data dialog; 2) the coordination number; 3) the type number of the central atom; and 4) the first type number for ligands (which is often the only one).
Note that when Urey-Bradley models 1) or 2) are in effect (see the Urey-Bradley Data dialog), polyhedra with coordination number other than 4 or 6 do not use kappa. Thus such polyhedra will not have an entry for kappa in this list.