Effective Spatial Averaging for NMR Second Moment Calculation

✍ Scribed by Roman Goc

• Book ID: 102595618
• Publisher: Elsevier Science
• Year: 1998
• Tongue: English
• Weight: 106 KB
• Volume: 132
• Category: Article
• ISSN: 1090-7807
• DOI: 10.1006/jmre.1998.1384

✦ Synopsis

A very effective method of spatial averaging for Van Vleck's The numerically calculated average F num would be equal to second moment calculation for polycrystalline materials with inthe exact average F V in the unrealistic limit N r ϱ and ternal rotation of atoms is presented. Compared with other meth-M r ϱ. For any practical calculations, where the evaluation ods of spatial averaging described in literature, the method preof function F(lDg, kDd) might require minutes of CPU sented in this paper is tens of times faster. The details of calculatime for every value of l and k, N and M must be kept as tion presented in this paper enable their immediate application in small as possible from the accuracy point of view. Different numerical evaluation of the second moment for structures with methods were developed to optimize the relation between internal reorientation. ᭧ 1998 Academic Press the values of N, M, and the final accuracy. One of the latest papers concerning this problem (1) gives references to the previously presented solutions.