Note that the optimization is not constrained to keeping shifts or coupling constants of degenerate spins the same, so that after optimization degenerate spins may have slightly different values. These can be adjusted manually and, if desired, the optimization repeated. The time required to calculate a spectrum depends on the number of spins and on the speed of the computer. Calculations involving up to about 8 spins take just a few seconds, but the time required goes up dramatically for each spin added. A 10-spin simulation takes about a minute on a reasonably fast Pentium.
Optimization is therefore practical only on smaller spin systems.
The following subcommands are active within the NMR Simulation subroutine. They are single-letter commands which are executed immediately. All commands can also be accessed via the menus. G Get simulation data from file Q Quit drawing spectrum. Interrupts a slow drawing operation.