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IN1-Lagrange

Large Area GRaphite ANalyser for Genuine Excitations

Applications

The two spectrometers of IN1 are used in the studies of excitation spectra in solids and liquids which demand high neutron energies available from the hot source.

IN1-TAS is convenient for measurements of dispersion relations of lattice and magnetic excitations with high energies. An example of investigation of magnon dynamics in iron metal is given in example 1. Another field of application of IN1-TAS is Brillouin scattering in liquids when high neutron energies are used to extend accessible dynamic range for measurements of thermal excitations with small momentum transfers.

IN1-BeF is optimized for the phonon density-of-states measurements, studies of molecular dynamics and atomic bonding in Hydrogen-containing matter, materials and compounds - hydrides, zeolites and catalysts, biological matter etc. High quality spectra can be recordered even from small samples due to very high luminosity of this spectrometer. An example of a recent study of metastable metal hydrides synthesized under extreme conditions is shown in example 4.

IN1 is mainly devoted to the study of excitation spectra in solids and liquids which demand high neutron energies available from the hot source. IN1-Lagrange will extend the application of its Be-filter option (phonon density-of-states measurements, studies of molecular dynamics and atomic bondings, etc.)

Example 1

Inelastic structure factor of heavy water D20 measured at IN1 with 120 meV final energy

The combination of Cu(331) monochromator and Cu(400) analyzer, with collimations of 20’ after the monochromator, sample and analyser, and a 1m long evacuated flight-path around the sample, allowed for the observation of an additional inelastic contribution, other than the collective one, centred around 5-6 meV

Ref.: C.Petrillo et al, Phys. Rev. E, 2000, vol.62, p.3611-3618)

Example 2

Top panel:
scattering function for a series of 3d- and 4dmetal hydrides;

Bottom panel:
energies of fundamental vibrations of hydrogen as a function of Me-H distance – a striking difference between mono-hydrides (closed symbols) and di-hydrides (crosses) is demonstrated

Ref.: A.I.Kolesnikov et al, Physica B, 2002, vol.316-317, p.158-161)