Single-particle and collective excitations of polar water molecules confined in nano-pores within a cordierite crystal lattice

M. A. Belyanchikov, Z. V. Bedran, M. Savinov, P. Bednyakov, P. Proschek, J. Prokleska, V. A. Abalmasov, E. S. Zhukova, V. G. Thomas, A. Dudka, A. Zhugayevych, J. Petzelt, A. S. Prokhorov, V. B. Anzin, R. K. Kremer, J. K.H. Fischer, P. Lunkenheimer, A. Loidl, E. Uykur, M. DresselB. Gorshunov

Результат исследования: Научные публикации в периодических изданияхстатьярецензирование


Recently, the low-temperature phase of water molecules confined within nanocages formed by the crystalline lattice of water-containing cordierite crystals has been reported to comprise domains with ferroelectrically ordered dipoles within the a, b-planes which are antiferroelectrically alternating along the c-axis. In the present work, comprehensive broad-band dielectric spectroscopy is combined with specific heat studies and molecular dynamics and Monte Carlo simulations in order to investigate in more detail the collective modes and single-particle excitations of nanoconfined water molecules. From DFT-MD simulations we reconstruct the potential-energy landscape experienced by the H2O molecules. A rich set of anisotropic temperature-dependent excitations is observed in the terahertz frequency range. Their origin is associated with the complex rotational/translational vibrations of confined H2O molecules. A strongly temperature dependent relaxational excitation, observed at radio-microwave frequencies for the electric field parallel to the crystallographic a-axis, E||a is analyzed in detail. The temperature dependences of loss-peak frequency and dielectric strength of the excitation together with specific heat data confirm a ferroelectric order-disorder phase transition at T0 ≈ 3 K in the network of H2O dipoles. Additional dielectric data are also provided for polarization E||b, too. Overall, these combined experimental investigations enable detailed conclusions concerning the dynamics of the confined water molecules that develop within their microscopic energy landscapes.

Язык оригиналаанглийский
Страницы (с-по)6890-6904
Число страниц15
ЖурналPhysical Chemistry Chemical Physics
Номер выпуска11
СостояниеОпубликовано - 21 февр. 2022

Предметные области OECD FOS+WOS



Подробные сведения о темах исследования «Single-particle and collective excitations of polar water molecules confined in nano-pores within a cordierite crystal lattice». Вместе они формируют уникальный семантический отпечаток (fingerprint).