Understanding the molecular behavior of water in spatially restricted environments is key to better understanding its role in many biological, chemical and geological processes. Here we examine the translational diffusion of water confined to a variety of substrates, from flat surfaces to nanoporous media, in the context of a recently proposed universal scaling law [Chiavazzo et al., Nat. Comm. 5, 1 (2014)] [1]. Using over a dozen previous neutron scattering results, we test the validity of this law, evaluating separately the influence of the hydration amount, and the effects of the size and morphology of the confining medium. Additionally, we investigate the effects of changing instrument resolutions and fitting models on the applicability of this law. Finally, we perform quasi-elastic neutron scattering measurements on water confined inside nanoporous silica to further evaluate this predictive law, in the temperature range 250 ≤ T ≤ 290 K.

The symmetry of local moments plays a defining role in the nature of exotic grounds states stabilized in frustrated magnetic materials. We present inelastic neutron scattering (INS) measurements of the crystal electric field (CEF) excitations in the family of compounds MgRE2Se4 (RE ∈ {Ho, Tm, Er and Yb}). These compounds form in the spinel structure, with the rare earth ions comprising a highly frustrated pyrochlore sublattice. Within the symmetry constraints of this lattice, we fit both the energies and intensities of observed modes in the INS spectra to determine the most likely CEF Hamiltonian for each material and comment on the ground state wavefunctions in the local electron picture. In this way, we experimentally confirm MgTm2Se4 has a non-magnetic ground state, and MgYb2Se4 has effective S = 1 2 spins with g = 5.188(79) and g ⊥ = 0.923(85) µB. The spectrum of MgHo2Se4 indicates a ground state doublet containing Ising spins with g = 2.72(46), though low-lying CEF levels are also seen at thermally accessible energies δE = 0.591(36), 0.945(30) and 2.88(7) meV, which can complicate interpretation. These results are used to comment on measured magnetization data of all compounds, and are compared to published results on the material MgEr2Se4. :1906.10767v1 [cond-mat.dis-nn] arXiv

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Transport measurements (electrical resistivity, Seebeck coefficient, and thermal conductivity) in the temperature range 80-500 K are presented for single crystals of the quasi-one-dimensional (Q1D) semiconductor Li 0.33 MoO 3. Opposite signs are observed for the Seebeck coefficient along the trinclinic a and c axes, with S c À S a ' 250 lV/K near room temperature and '100 lV/K at 380 K. The thermal conductivity at room temperature in the a-c planes was $2 W/m K and $10 times smaller along b*. A weak structural anomaly at T s % 355 K, identified in the temperaturedependent lattice constants, coincides with anomalies in the electrical properties. Analysis of the electronic transport at T > T s favors an intrinsic semiconductor picture for transport along the most conducting Q1D axis and small-polaronic transport along the other directions, providing insight into the origin of the Seebeck anisotropy. V