Reversible First-Order Single Crystal to Single Crystal Thermal Phase Transition in [(CH3)3CNH3]4[V4O12]
[EN] The well-known compound tetrakis(tert-butylammonium)-cyclo-tetrametavanadate (V), [(CH3)3CNH3]4[V4O12] (1h_RT), which crystallizes in the tetragonal I4/m space group, undergoes an irreversible solid state transformation upon heating, constituting one of the few examples in which the initial and...
| Autores: | , , , , , , , |
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| Tipo de recurso: | artículo |
| Fecha de publicación: | 2022 |
| País: | España |
| Institución: | Universidad del País Vasco |
| Repositorio: | Addi. Archivo Digital para la Docencia y la Investigación |
| OAI Identifier: | oai:addi.ehu.eus:10810/57354 |
| Acceso en línea: | http://hdl.handle.net/10810/57354 |
| Access Level: | acceso abierto |
| Palabra clave: | polyoxovanates SCSC transformations thermal and structural characterization |
| Sumario: | [EN] The well-known compound tetrakis(tert-butylammonium)-cyclo-tetrametavanadate (V), [(CH3)3CNH3]4[V4O12] (1h_RT), which crystallizes in the tetragonal I4/m space group, undergoes an irreversible solid state transformation upon heating, constituting one of the few examples in which the initial and the final stages are structurally characterized by sc-XRD. Now, we observed the ability of the same compound to undergo an additional single-crystal-to-single-crystal (SCSC) transformation upon thermal stimuli, but this time at low temperatures (153 K). Compound 1h_RT contains a discrete unprotonated [V4O12]4− tetrahedral anion in which V and O bridging atoms are coplanar. In both phases, these tetrameric anions are linked through tert-butylammonium cations in an extensive network of hydrogen bonds, but at low temperatures, this phase loses its characteristic O-V-O coplanarity, with the resulting rearrangement of the crystal packing and hydrogen-bond network which provide its reversibility at low temperatures. Again, the initial and final stages have been characterized structurally by sc-XRD. |
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