Interplay between Local Structure and Nuclear Dynamics in Tungstic Acid: A Neutron Scattering Study

We provide an exhaustive characterization of structural properties and nuclear dynamics in tungstic acid (WO3·H2O). To this end, we employ neutron X-ray diffraction (ND XRD) combined with inelastic scattering (INS) Compton (NCS) experiments, corroborate the analysis extensive ab initio modeling. The first step our is elucidation crystal structure based on refinement low-temperature powder ND data, extending knowledge gained from XRD a mineral specimen tungstite. These results are confronted INS experiments zero-temperature phonon calculations. reveals inconsistency definition confined water respect to crystallographic also showing concomitant failure calculations due strongly anharmonic confining potential. Extending computational route toward MD (AIMD) simulations allows us probe different configurations provides improved description vibrational as compared high-resolution nevertheless, requiring use effective classical temperatures. both NCS data remarkable similarity earlier reported for single-wall carbon nanotubes (SWNT), which has been qualitatively described new phase ice. Our strong two-dimensional hydrogen-bonding network, similar shell model SWNT. show narrowing hydrogen momentum distribution reference calculations, indicating great deal conformational freedom spatial delocalization protons ground state system, clear signature quantum character nuclei.