MOLECULAR STRUCTURE AND GRAY AND CRUICKSHANK'S METHOD OF CALCULATING MOLECULAR DIAMAGNETISM. PART I. UREA AND SUBSTITUTED' UREAS

The magnetic susceptibility values for urea and substituted ureas have been calculated according to Gray and Cruickahank's method on the basis of evidence furnished by X-ray study of the crystal structure of urea. It has been shown that the calculated value differs considerably from the experi­mental one. The structures considered by Clow and his method of calculating the susceptibility value have been criticised and proved to be untenable, and the agreement obtained between the calculated sad the experimental values by him has thus been shown to have little or no significance.