, ▁impro ving ▁the ▁accuracy ▁of ▁phase ▁determ ination ▁algorithms . ▁Similarly , ▁more ▁higher ▁order ▁La ue ▁zone ▁( H OL Z ) ▁ref lections ▁are ▁present ▁in ▁the ▁pattern , ▁which ▁can ▁provide ▁more ▁complete ▁information ▁about ▁the ▁three - dimensional ▁nature ▁of ▁reci pro cal ▁space , ▁even ▁in ▁a ▁single ▁two - dimensional ▁P ED ▁pattern . ▁ ▁Pract ical ▁robust ness : ▁P ED ▁is ▁less ▁sensitive ▁to ▁small ▁experimental ▁variations ▁than ▁other ▁electron ▁diff raction ▁techniques . ▁Since ▁the ▁measurement ▁is ▁an ▁average ▁over ▁many ▁incident ▁beam ▁directions , ▁the ▁pattern ▁is ▁less ▁sensitive ▁to ▁slight ▁mis orientation ▁of ▁the ▁zone ▁axis ▁from ▁the ▁opt ic ▁axis ▁of ▁the ▁mic ros cope , ▁and ▁resulting ▁P ED ▁patterns ▁will ▁generally ▁still ▁display ▁the ▁zone ▁axis ▁symmetry . ▁The ▁patterns ▁obtained ▁are ▁also ▁less ▁sensitive ▁to ▁the ▁thick ness ▁of ▁the ▁sample , ▁a ▁parameter ▁with ▁strong ▁influence ▁in ▁standard ▁electron ▁diff raction ▁patterns . ▁ ▁Very ▁small ▁pro be ▁size : ▁Because ▁x - ray s ▁interact ▁so ▁weak ly ▁with ▁matter , ▁there ▁is ▁a ▁minimum ▁size ▁limit ▁of ▁approximately ▁ 5   µ m ▁for ▁single ▁cry st als ▁that ▁can ▁be ▁exam ined ▁via ▁x - ray ▁diff raction ▁methods . ▁In ▁contrast , ▁electrons ▁can ▁be ▁used ▁to ▁pro be ▁much ▁smaller ▁n ano - c ry st als ▁in ▁a ▁T EM . ▁In ▁P ED , ▁the ▁pro be ▁size ▁is ▁limited ▁by ▁the ▁l ens ▁aber r ations ▁and ▁sample