Anion–Cation Recognition Pattern, Thermal Stability and DFT-Calculations in the Crystal Structure of H2dap[Cd(HEDTA)(H2O)] Salt (H2dap = H2(N3,N7)-2,6-Diaminopurinium Cation) Belmont Sánchez, Jeannette Carolina Ruiz González, Noelia Matilla Hernández, Antonio Niclos Gutiérrez, Juan EDTA 2,6-diaminopurine Cadmium Co-crystal H-bonding π–π stacking We thank the Centre de Tecnologies de la Informació (CTI), Universitat de les Illes Balears for computational facilities. We also thank all projects for financial support. The proton transfer between equimolar amounts of [Cd(H2EDTA)(H2O)] and 2,6-diaminopurine (Hdap) yielded crystals of the out-of-sphere metal complex H2(N3,N7)dap [Cd(HEDTA)(H2O)]·H2O (1) that was studied by single-crystal X-ray diffraction, thermogravimetry, FT-IR spectroscopy, density functional theory (DFT) and quantum theory of “atoms-in-molecules” (QTAIM) methods. The crystal was mainly dominated by H-bonds, favored by the observed tautomer of the 2,6-diaminopurinium(1+) cation. Each chelate anion was H-bonded to three neighboring cations; two of them were also connected by a symmetry-related anti-parallel π,π-staking interaction. Our results are in clear contrast with that previously reported for H2(N1,N9)ade [Cu(HEDTA) (H2O)]·2H2O (EGOWIG in Cambridge Structural Database (CSD), Hade = adenine), in which H-bonds and π,π-stacking played relevant roles in the anion–cation interaction and the recognition between two pairs of ions, respectively. Factors contributing in such remarkable differences are discussed on the basis of the additional presence of the exocyclic 2-amino group in 2,6-diaminopurinium(1+) ion. 2020-06-12T12:47:54Z 2020-06-12T12:47:54Z 2020-04 info:eu-repo/semantics/article Belmont-Sánchez, J. C., Ruiz-González, N., Frontera, A., Matilla-Hernández, A., Castiñeiras, A., & Niclós-Gutiérrez, J. (2020). Anion–Cation Recognition Pattern, Thermal Stability and DFT-Calculations in the Crystal Structure of H2dap [Cd (HEDTA)(H2O)] Salt (H2dap= H2 (N3, N7)-2, 6-Diaminopurinium Cation). Crystals, 10(4), 304. [doi:10.3390/cryst10040304] http://hdl.handle.net/10481/62455 doi:10.3390/cryst10040304 eng http://creativecommons.org/licenses/by/3.0/es/ info:eu-repo/semantics/openAccess Atribución 3.0 España MDPI