The origin of the conformational preference of N,N'-diaryl-N,N'-dimethyl ureas Clayden, Jonathan ; Hennecke, Ulrich ; Vincent, Mark A. ; Hillier, Ian H. ; Helliwell, Madeleine Abstract Publication: Physical Chemistry Chemical Physics (Incorporating Faraday Transactions) Pub Date: 2010 DOI: 10.1039/c0cp00571a Bibcode: 2010PCCP...1215056C