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Infrared absorption spectroscopy study of endohedral water molecule in a solid mixture of H$_2$O@C$_{60}$ and C$_{60}$ was carried out at liquid helium temperature. From the evolution of the spectra during the ortho-para conversion process, the spectral lines were identified as para- and ortho-water transitions. Eight vibrational transitions with rotational side peaks were observed in the mid-infrared: $\omega_1$, $\omega_2$, $\omega_3$, $2\omega_1$, $2\omega_2$, $\omega_1 +\omega_3$, $\omega_2 +\omega_3$, and $2\omega_2+\omega_3$. The vibrational frequencies $\omega_2$ and 2$\omega_2$ are lower by 1.6\% and the rest by 2.4\%, as compared to free \water/. A model consisting of a rovibrational Hamiltonian with the dipole and quadrupole moments of water interacting with the crystal field was used to fit the infrared absorption spectra. The electric quadrupole interaction with the crystal field lifts the degeneracy of the rotational levels. The finite amplitudes of the pure $v_1$ and $v_2$ vibrational transitions are consistent with the interaction of the water molecule dipole moment with a lattice-induced electric field. The permanent dipole moment of encapsulated \water/ is found to be $0.5\pm 0.1$ D as determined from the far-infrared rotational line intensities. The translational mode of the quantized center of mass motion of \water/ in the molecular cage of C$_{60}$ was observed at 110cm$^{-1}$ (13.6meV).

Dementia is a major challenge for society and its impact will grow in the future. Informal care is an essential part of dementia care. Previous studies considered informal care as a whole and not by its components.We aimed to assess the degree of association between specific informal care services and dementia.This analysis is based on data from the seventh wave of the AgeCoDe/AgeQualiDe study. Dementia was diagnosed based on the DSM-IV criteria. Severity of dementia was assessed and categorized by means of the Clinical Dementia Rating and eight individual informal care services were considered. Logistic regression models were used to assess associations.Of the 864 participants 18% suffered from dementia (very mild: 4%; mild: 6%; moderate: 5%; severe: 3%). All informal care services were significantly associated with dementia, with an emphasis on 'supervision', 'regulation of financial matters' and 'assistance in the intake of medication'. Considering different degrees of dementia severity, similar results arose from the analyses. All three aforementioned services showed a pronounced association with all degrees of dementia severity, except for supervision and very mild dementia.The provision of all types of informal care services is associated with dementia. The association is pronounced for services that can be more easily integrated into the daily routines of the informal caregiver. Policy makers who plan to integrate informal care into the general care arrangements for dementia should consider this.

The photoexcitation of functionalized fullerenes to their paramagnetic triplet electronic state can be studied by pulsed electron paramagnetic resonance (EPR) spectroscopy, whereas the interactions of this state with the surrounding nuclear spins can be observed by a related technique: electron nuclear double resonance (ENDOR). In this study, we present EPR and ENDOR studies on a functionalized exohedral fullerene system, dimethyl[9-hydro (C60-Ih)[5,6]fulleren-1(9H)-yl]phosphonate (DMHFP), where the triplet electron spin has been used to hyperpolarize, couple and measure two nuclear spins. We go on to discuss the extension of these methods to study a new class of endohedral fullerenes filled with small molecules, such as H₂@C₆₀, and we relate the results to density functional calculations.

We report on the dynamics of two hydrogen isotopomers, D2 and HD, trapped in the molecular cages of a fullerene C60 molecule. We measured the infrared spectra and analyzed them using a spherical potential for a vibrating rotor. The potential, vibration-rotation Hamiltonian, and dipole moment parameters are compared with previously studied H2@C60 parameters [M. Ge, U. Nagel, D. Hüvonen, T. Rõõm, S. Mamone, M. H. Levitt, M. Carravetta, Y. Murata, K. Komatsu, J. Y.-C. Chen, and N. J. Turro, J. Chem. Phys. 134, 054507 (2011)10.1063/1.3535598]. The isotropic part of the potential is similar for all three isotopomers. In HD@C60, we observe mixing of the rotational states and an interference effect of the dipole moment terms due to the displacement of the HD rotation center from the fullerene cage center.

We have measured the temperature dependence of the infrared spectra of a hydrogen molecule trapped inside a C60 cage, H2@C60, in the temperature range from 6 to 300 K and analyzed the excitation spectrum by using a five-dimensional model of a vibrating rotor in a spherical potential. The electric dipole moment is induced by the translational motion of endohedral H2 and gives rise to an infrared absorption process where one translational quantum is created or annihilated, ?N = ±1. Some fundamental transitions, ?N = 0, are observed as well. The rotation of endohedral H2 is unhindered but coupled to the translational motion. The isotropic and translation–rotation coupling part of the potential are anharmonic and different in the ground and excited vibrational states of H2. The vibrational frequency and the rotational constant of endohedral H2 are smaller than those of H2 in the gas phase. The assignment of lines to ortho- and para-H2 is confirmed by measuring spectra of a para enriched sample of H2@C60 and is consistent with the earlier interpretation of the low temperature infrared spectra [Mamone et al., J. Chem. Phys. 130, 081103 (2009)].

[Longitudinal Predictors of the Need for Care].