Combined Single-Crystal XRD,solution 13C and ^(195)Pt NMR,solid-state ^(195)Pt NMR and UV-vis measurements,together with comprehensive(TD)DFT calculations,are used to describe the supramolecular interactions and seque...Combined Single-Crystal XRD,solution 13C and ^(195)Pt NMR,solid-state ^(195)Pt NMR and UV-vis measurements,together with comprehensive(TD)DFT calculations,are used to describe the supramolecular interactions and sequential concerted structural transformation occurring in a{PPh4^(+);[Pt(CN)_(4)]^(2-);TCP;CH_(2)Cl_(2)}supramolecular system(TCP-tetracyanopyrazine).In the solid-state,a mixture of needle-like co-crystals first appears,(PPh_(4))_(2){[TCP][Pt(CN)_(4)]}(1)and(PPh_(4))_(2){[TCP][Pt(CN)_(4)]}·2CH_(2)Cl_(2)(2),and subsequent recrystallization leads to block-shaped co-crystals of(PPh_(4))_(2){[TCP]2[Pt(CN)_(4)]}·2CH_(2)Cl_(2)(3),wherein double{[Pt(CN)_(4)]^(2-);TCP}and triple{[Pt(CN)_(4)]^(2-);TCP;CH_(2)Cl_(2)}and{PPh4^(+);[Pt(CN)_(4)]^(2-);TCP}synthons present either in 1 or 2 are reproduced in 3.The structural pathway(1,2→3)is accompanied by a 1D-to-2D modular evolution of anion-πinteractions between[Pt(CN)_(4)]^(2-)andπ-acidic TCP that seems to be driven,as indicated by calculations,not by maximizing their strength but rather by optimizing other crystal interactions,e.g.between PPh4^(+)cations.Formation of the corresponding{[Pt(CN)_(4)]^(2-);π-acid}anion-πcontacts in solution is evidenced by 13C NMR shifts and by new low-energy electronic absorption in the visible region(UV-vis).Finally,a combined solution/solid-state ^(195)Pt NMR approach is used for the first time to shed light on the geometry and interactions involving such aggregates;it shows that the degree of trapping of[Pt(CN)_(4)]^(2-)near aπ-acidic surface can be monitored by ^(195)Pt NMR chemical shifts.The results give fresh insight into block arrangement tactics and characterization of hybrid organic-inorganic co-crystal salts,and into aggregation controlled properties.展开更多
基金supported by the National Science Center in Poland(grant OPUS 8,UMO 2014/15/B/ST5/02098)E.Kuzniak acknowledges the fellowship within the project no.POWR.03.02.00-00-I013/16.J.Hooper is grateful for the financial support from the Ministry of Science and Higher Education in Poland(Outstanding Young Scientist scholarship)+2 种基金R.Podgajny and S.Ferlay acknowledge the support from French Government and the French Embassy in Poland(the BGF Fellowship)Measurements were carried out with the equipment purchased thanks to the support of the European Regional Development Fund in the framework of the Polish Innovation Economy Operational Program(contract no.POIG.02.01.00-12-023/08)the PL-Grid Infrastructure and the ACC Cyfronet AGH(Krakow,Poland)for computational resources.
文摘Combined Single-Crystal XRD,solution 13C and ^(195)Pt NMR,solid-state ^(195)Pt NMR and UV-vis measurements,together with comprehensive(TD)DFT calculations,are used to describe the supramolecular interactions and sequential concerted structural transformation occurring in a{PPh4^(+);[Pt(CN)_(4)]^(2-);TCP;CH_(2)Cl_(2)}supramolecular system(TCP-tetracyanopyrazine).In the solid-state,a mixture of needle-like co-crystals first appears,(PPh_(4))_(2){[TCP][Pt(CN)_(4)]}(1)and(PPh_(4))_(2){[TCP][Pt(CN)_(4)]}·2CH_(2)Cl_(2)(2),and subsequent recrystallization leads to block-shaped co-crystals of(PPh_(4))_(2){[TCP]2[Pt(CN)_(4)]}·2CH_(2)Cl_(2)(3),wherein double{[Pt(CN)_(4)]^(2-);TCP}and triple{[Pt(CN)_(4)]^(2-);TCP;CH_(2)Cl_(2)}and{PPh4^(+);[Pt(CN)_(4)]^(2-);TCP}synthons present either in 1 or 2 are reproduced in 3.The structural pathway(1,2→3)is accompanied by a 1D-to-2D modular evolution of anion-πinteractions between[Pt(CN)_(4)]^(2-)andπ-acidic TCP that seems to be driven,as indicated by calculations,not by maximizing their strength but rather by optimizing other crystal interactions,e.g.between PPh4^(+)cations.Formation of the corresponding{[Pt(CN)_(4)]^(2-);π-acid}anion-πcontacts in solution is evidenced by 13C NMR shifts and by new low-energy electronic absorption in the visible region(UV-vis).Finally,a combined solution/solid-state ^(195)Pt NMR approach is used for the first time to shed light on the geometry and interactions involving such aggregates;it shows that the degree of trapping of[Pt(CN)_(4)]^(2-)near aπ-acidic surface can be monitored by ^(195)Pt NMR chemical shifts.The results give fresh insight into block arrangement tactics and characterization of hybrid organic-inorganic co-crystal salts,and into aggregation controlled properties.
