有的文献报道，在合成单晶时，用羧酸做配体，水热或溶剂热的方法合成，有时候要加那么一点点硝酸，不知道这样做的目的是什么？如下边的：To prepare crystals of JOU-34, a mixture of Zn(NO3)2⋅6H2O (0.045 mmol, 13.12 mg), H4TBAPy (0.015 mmol, 10.27 mg), DMF (2.5 mL), and HNO3 (60 μL, 65 wt%) were ultrasonic treated for 5 min, transferred into a 10 mL pressure-resistant glass bottle, and then heated at 120 ◦C for 72 h. Yellow block crystals were isolated by filtrating, washing with fresh DMF, and drying under air. H4TBAPy= 1,3,6,8-tetrakis (p-benzoic acid) pyrene
