Quadrupolar interaction...

Quadrupolar tensor definition :
  • principal values are sorted |Vyy|<=|Vxx|<=|Vzz| note that Vxx and Vyy have signs opposite to that of Vzz - usually NMR is not sign sensitive for EFG
  • Vzz+Vxx+Vyy=0
  • etaQ is the anisotropy of the Quadrupolar tensor etaQ=Vyy-Vxx/Vzz  with 0<=EtaQ<=1
  • and thus Vxx=1/2 (-EtaQ-1)Vzz  and Vyy=1/2 (EtaQ-1)Vzz

 Example :  2D static spectrum of Plexiglass  
 Example :  2D MAS spectrum of Methiodine fitted to 1st order  
 Example :  23Na MAS spectrum of Sodium Nitrate NaNO3  
 Example :  23Na MAS spectrum of Nasicon - central transition fitted with a 2nd order quadrupolar lineshape  
 Example :  27Al MAS 400MHz spectrum of YAG fitted with 1st order quadrupolar for AlO6 and 2nd order quadrupolar for AlO4  
 Example :  27Al 1D Spectrum of Glass with AlO4/AlO5/AlO6 sites  
 Example :  87Rb MQMAS spectrum of RbNO3  
 Example :  27Al Syncrhonized MQMAS  
 Example :  27Al STMAS Spectrum of A9B2 at 830MHz