Thermal Behavior of Tetrahydropyran‐Intercalated VOPO₄: Structural and Dynamics Study

Abstract

Keywords: Intercalations / NMR spectroscopy / IR spectroscopy / Thermal behavior / Quantum chemical calculationsThe thermal behavior of tetrahydropyran-(THP-)intercalated VOPO 4 was probed by an extensive combination of experimental methods (XRD, DSC, FTIR, solid-state NMR) and quantum chemical calculations. Two temperature-induced transitions were detected and all polymorphs exhibit a high degree of molecular order and tight packing of THP in VOPO 4 . The first reversible thermal transition at around 100°C was attributed to boat/chair conformation changes of the THP molecules. Most probably, a low-temperature boat conformation of the guest molecules present in the interlayer space of VOPO 4 changes to a high-temperature chair confor-

Intercalation chemistry of layered vanadyl phosphate: a review

“…Both steps are reversible during cooling. The first reversible thermal transition was attributed to the boat/ chair conformation changes of the tetrahydropyran molecules which were confirmed by variable-temperature 13 C CP/MAS NMR spectroscopy [95]. The second change is probably caused by weakening of the donor-acceptor bond between the oxygen of tetrahydropyran molecule and the vanadium atom of the host.…”

Two-dimensional mesoporous vanadium phosphate nanosheets through liquid crystal templating method toward supercapacitor application

“…The pronounced band at 683 cm -1 can be credited to the characteristic V-O-P bending vibration [32,[45][46][47]. Two strong bands at 1083 cm -1 and 952 cm -1 and the adjacent shoulder at 994 cm -1 are attributed to the asymmetric stretching mode of PO 4 tetrahedral group, while the small band at 1169 cm -1 originates from the anti-symmetric stretching mode of PO 4 group [48][49][50][51]. Additionally, one weak band is observed at 1037 cm -1 , which may be assigned to the stretching vibration of V=O group [48,[52][53].…”