Partial Order-Disorder Transformation of Interpenetrated Porous Coordination Polymers

Controlling interpenetration and flexibility behaviors is intriguing and fundamental for porous coordination polymers.We report exceptional interpenetration behaviors involving controllable partial order–disorder structural transformations.A new bis-benzotriazolate ligand(NaH2sbbta)with a twisted and anionic backbone was designed and synthesized.The solvothermal reaction of ZnCl_(2) and NaH_(2)sbbta yielded(Et_(2)NH_(2))_(3)[Zn_(5)Cl_(4)(sbbta)_(3)]·6DEF(2)possessing two-fold interpenetrated anionic pcu networks with symmetry,shape,and charge different from the known analogues.More interestingly,powder and single-crystal X-ray diffractions showed that 2 can undergo solvent-induced structural transformation to form a noninterpenetrated anionic pcu network with larger pores(1).Consequently,1/2 can selectively adsorb/exchange cationic dyes fromneutral and anionic dyes with tunable size selectivity.However,since the transformations are reversible without obvious change of crystal sizes,the network that disappeared in X-ray crystallography should be mainly disordered rather than decomposed.Further,the structural transformations can be suppressed by thermal decomposition/removal of Et_(2)NH_(2)^(+)/Et_(2)NH.Computational simulations indicate that the ordered and disordered structures are stabilized by relatively large and small solvent molecules,respectively.