Behavior of individual molecules of normal and heavy water in beryl single crystals was studied by H and H nuclear magnetic resonance spectroscopy. From temperature dependences of the spectra, we deduce that type-I water molecules embedded in the beryl voids are oriented quite differently from the view established in the literature: Different from the earlier assumptions, their H-H lines deviate by about 18° from the hexagonal axis. We suggest that this is due to the molecules attaching to the oxygen atoms forming the beryl structural voids by a hydrogen bond.
View Article and Find Full Text PDFWe have studied the radio frequency dielectric response of a system consisting of separate polar water molecules periodically arranged in nanocages formed by the crystal lattice of the gemstone beryl. Below = 20-30 K, quantum effects start to dominate the properties of the electric dipolar system as manifested by a crossover between the Curie-Weiss and the Barrett regimes in the temperature-dependent real dielectric permittivity ε'(). When analyzing in detail the temperature evolution of the reciprocal permittivity (ε') down to ≈ 0.
View Article and Find Full Text PDFLow-energy excitations of a single water molecule are studied when confined within a nano-size cavity formed by the ionic crystal lattice. Optical spectra are measured of manganese doped beryl single crystal Mn:Be3Al2Si6O18, that contains water molecules individually isolated in 0.51 nm diameter voids within the crystal lattice.
View Article and Find Full Text PDFWhen water is confined to nanocavities, its quantum mechanical behavior can be revealed by terahertz spectroscopy. We place H2O molecules in the nanopores of a beryl crystal lattice and observe a rich and highly anisotropic set of absorption lines in the terahertz spectral range. Two bands can be identified, which originate from translational and librational motions of the water molecule isolated within the cage; they correspond to the analogous broad bands in liquid water and ice.
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