Preset

You should always start by choosing the proper preset.

ADF has many different modes of operation. ADFinput presents the correct settings for some common calculations together as 'presets'.

So to optimize the geometry of the ethanol molecule we just choose the proper preset:

Select the 'Geometry Optimization' preset from the 'Preset' menu.

Presets might change any number of input options. In this particular example, the main Task will change from 'Single Point' to 'Geometry Optimization'. You can easily see what fields have been updated by a preset: they are colored green.

If you would use this preset again later, the input values that are set by this preset will revert to the default values. If you made changes to those fields you will loose your those changes.

Note that you could also have chosen the 'Geometry Optimization Strict' preset from the 'Preset' menu. Using this preset strict convergence criteria are set and a higher integration accuracy is set, which means that the calculation may take (much) more time than using the 'Geometry Optimization' preset. The 'Geometry Optimization Strict' preset also sets the use of the new optimization method in delocalized coordinates, which is especially useful in case of weakly bound or floppy systems and/or if one requires strict convergence.