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The low-temperature state of the quantum spin liquid candidate κ-(BEDT-TTF)_{2}Cu_{2}(CN)_{3} emerges via an anomaly at T^{*}∼6 K. Although signatures of this anomaly have been revealed in various quantities, its origin has remained unclear. Here we report inelastic neutron scattering measurements on single crystals of κ-(BEDT-TTF)_{2}Cu_{2}(CN)_{3}, aiming at studying phonon renormalization effects at T^{*}. A drastic change was observed in the phonon damping across T^{*} for a breathing mode of BEDT-TTF dimers at E=4.7 meV. The abrupt change in the phonon damping is attributed to a phase transition into a valence bond solid state based on an effective model describing the spin-charge coupling in this dimer-Mott system.

Activated carbons are materials with relevance in different industrial applications. Due to the inherent complexity and heterogeneity of their structures, an easy assignment of the species present on their surface has a challenging result. Only recently, with the possibility to collect well-resolved inelastic neutron spectra and to simulate by DFT methods more or less extended graphitic clusters, this task is starting to become feasible. Here we report our investigation on a steam activated carbon and we show that different vibrations in the region of out-of-plane C-H bending modes are specifically connected to hydrogen terminations belonging to extended and regular borders or to short and defective ones. Furthermore, simulations including heteroatoms such as oxygen allowed us to point out spectral regions with a contribution from carboxyl species.