▁of ▁the ▁diff raction ▁pattern . ▁Finally , ▁the ▁beam ▁is ▁pre cess ed ▁around ▁the ▁opt ic ▁axis ▁while ▁the ▁diff raction ▁pattern ▁is ▁collected ▁over ▁multiple ▁revolution s . ▁ ▁The ▁result ▁of ▁this ▁process ▁is ▁a ▁diff raction ▁pattern ▁that ▁consists ▁of ▁a ▁summ ation ▁or ▁integration ▁over ▁the ▁patterns ▁generated ▁during ▁pre cess ion . ▁While ▁the ▁geometry ▁of ▁this ▁pattern ▁matches ▁the ▁pattern ▁associated ▁with ▁a ▁normally ▁incident ▁beam , ▁the ▁intens ities ▁of ▁the ▁various ▁ref lections ▁approximate ▁those ▁of ▁the ▁kin emat ical ▁pattern ▁much ▁more ▁closely . ▁At ▁any ▁moment ▁in ▁time ▁during ▁pre cess ion , ▁the ▁diff raction ▁pattern ▁consists ▁of ▁a ▁La ue ▁circle ▁with ▁a ▁radius ▁equal ▁to ▁the ▁pre cess ion ▁angle , ▁ φ . ▁It ▁is ▁cru cial ▁to ▁note ▁that ▁these ▁snap sh ots ▁contain ▁far ▁fewer ▁strongly ▁excited ▁ref lections ▁than ▁a ▁normal ▁zone ▁axis ▁pattern ▁and ▁extend ▁farther ▁into ▁reci pro cal ▁space . ▁Thus , ▁the ▁composite ▁pattern ▁will ▁display ▁far ▁less ▁dynam ical ▁character , ▁and ▁will ▁be ▁well ▁su ited ▁for ▁use ▁as ▁input ▁into ▁direct ▁methods ▁calculations . ▁ ▁Adv antages ▁▁ ▁P ED ▁poss esses ▁many ▁advantage ous ▁attributes ▁that ▁make ▁it ▁well ▁su ited ▁to ▁investig ating ▁cry stal ▁structures ▁via ▁direct ▁methods ▁approaches : ▁▁ ▁Qu asi - kin emat ical ▁diff raction ▁patterns : ▁While ▁the ▁underlying ▁physics ▁of ▁the ▁electron ▁diff raction ▁is ▁still ▁dynam ical ▁in ▁nature , ▁the ▁conditions ▁used ▁to ▁collect ▁P ED