To add additional line broadening, you can arteficially broaden the spectra.   
Broadening of spectra in the fast motional limit is performed by convolution with either a lorentzian or gaussian line shape.
The full linewidth at half height has to be entered in kHz (I=1) or ppm (I=1/2). When a lorentzian lineshape has been selected, this corresponds to 2&sigma;, when gausssian is selected, it correspponds to 2&sigma;*sqrt(2log(2)). <p> For slow motion spectra Weblab calculates the time evoulution of the density operator and line broadening is taken into account by considering a uniform transversal relaxation time of the spin system independent of cone motion and sites. In praxis Weblab includes an exponential damping factor to the time signal corresponding to a lorentzian line broadening with LB = 2/T<sub>2</sub>, where LB ist the value for the full linewidth entered from the main menu.