In: Physical Review B: condensed matter and materials physics, 2011, vol. 83, no. 6, p. 064107
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In: The Journal of Physical Chemistry A, 2010, vol. 114, no. 37, p. 10117–10121
The hydrogen dynamics in solid and in liquid LiBH₄ was studied by means of incoherent quasielastic neutron scattering. Rotational jump diffusion of the BH₄⁻ subunits on the picosecond scale was observed in solid LiBH₄. The characteristic time constant is significantly shortened when the system transforms from the low-temperature phase to the high-temperature phase at 383 K. In the molten...
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In: The Journal of Physical Chemistry C, 2010, vol. 114, no. 15, p. 7173-7177
We investigate the stability and hydrogen desorption of NaBH₄. Dynamic pcT (pressure, concentration, and temperature) measurements under constant hydrogen flows are used to determine thermodynamic parameters of reaction. From the van’t Hoff equation the enthalpy and entropy of reaction, −108 ± 3 kJ mol⁻¹ of H₂ and 133 ± 3 J K⁻¹ mol⁻¹ of H₂ released, are obtained,...
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In: The Journal of Physical Chemistry C, 2009, vol. 113, no. 39, p. 17223–17230
We have solved and refined the crystal structure of the orthorhombic γ-phase of Ca(BD₄)₂ by combined synchrotron X-ray powder diffraction, neutron powder diffraction, and ab initio calculations. Among five structural candidates giving the same quality of the fit of the diffraction data, the structural model with the highest symmetry and space group Pbca is the...
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In: Physical Review B, 2008, vol. 78, no. 09, p. 094302
We report on neutron powder-diffraction experiments, inelastic incoherent neutron-scattering experiments, and density-functional calculations on dynamics, order and disorder properties of LiBH4 and LiBD4. From refinement of LiBD4 structure at 10 and 302 K, we found an almost ideal tetrahedral geometry of BD4 ions (difference between shortest and longest interatomic distances is less than 4% for...
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In: Materials Science and Engineering B, 2004, vol. 108, p. 9-18
The challenge in the research on hydrogen storage materials is to pack hydrogen atoms or molecules as close as possible. Hydrogen absorbed in metals can reach a density of more than 150 kg m⁻³ (e.g. Mg₂FeH₆ or Al(BH₄)₃) at atmospheric pressure. For metallic hydrides, however, due to the large atomic mass of the transition metals the gravimetric hydrogen density is limited to less than...
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