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The generalized phonon density of states (PDOS) and the valence electron density of states (EDOS) of the amorphous Fe90-xCoxZr10 (x = 4, 10 and 40) alloys were measured at the room temperature by inelastic neutron-scattering and x-ray photoemission spectroscopy, respectively. Preliminary results show that the stronger the Invar effect, the softer is the PDOS in the low-energy region and the larger is the EDOS at the Fermi energy level. The enhancement of electron-phonon interaction was suggested to explain the low-energy phonon softening observed in Invar alloys.

Neutron diffraction study on the structure of Bi2Sr1.855Ca1.145Cu2O8 was carried out. Data refinements show that the average subcell structure for Bi2Sr1.855Ca1.145Cu2O8 is in the best fit of the space group Fmmm and the structure is described by alternate stacking of SrO-CuO2-Ca-CuO2-SrO slab and a double BiO layers. An oxygen layer sandwiched by the bismuth layers was confirmed.

The polycrystalline sample of (Bi–Pb)2Sr2Ca2Cu3O10 with Tc=107 K was prepared. The X-ray diffraction proved that the sample is single phase. The crystal structure study on the sample has been carried out by neutron diffraction. The result shows that its structure is tetragonal body-centre structure with space group of I4/mmm, containing a few oxygen atoms at 4e site in Bi–Pb layers.

Generalized phonon densities of states (PDOS) for amorphous Ｆｅ９０－ｘＣｏｘＺｒ１０（ｘ＝１０，４０） and Ｆｅ８０－ｙＣｒｙＰ１３Ｃ７（ｙ＝４，８） alloys have been deduced from inelastic neutron scattering experiments. And the softening phenomena of the PDOS in the energy region below 17 meV have been observed for the amorphous Invar alloys. The anomalies in the dynamics of Invar alloys were discussed, and preliminary results show that the phonon softening of the amorphous Invar alloys may closely connected with the enhanced electron—phonon interaction in lnvar alloys.

Inelastic neutron scattering spectra from superconducting material C-15 V2Zr, V2Zr0.95Nb0.05 and V2Hf0.5Zr0.5,V2Hf0.5Zr0.3Nb0.2 were measured by neutron time-of-flight method. It was found that the additional content of Nb influenced the superconducting transition temperature Tc and phonon frequencies of V2Zr1-xNbx in a way different from that of V2Hf0.5Zr0.5-xNbx. The Tc increases and the phonon frequencies "soften" with increasing x for the former, while the Tc slightly decreases and the phonon frequencies "harden" for the latter. The result that the phonon frequencies of V2Zr0.95Nb0.05 are softer than that of V2Zr is somewhat in contradiction with the previous results, which show that the magnetic susceptibilities decrease and the geometric mean phonon frequencies increase. The result that the phonon frequencies of V2Hf0.5Zr0.3Nb0.2 are harder than that of V2Hf0.5Zr0.5 can be considered as the result of hybridization of conduction band, which is studied for close-packed compounds by means of LMTO (linear combination of muffin-tin orbitals) method.

Inelastic neutron scattering spectra from C-15 phase superconducting alloys V2Hf, V2Ta, V2Hf0.8 Ta0.2, V2Zr0.5 Hf0.5 and V2Zr0.5 Hf0.33 Ta0.17 were measured by the neutron time-of-flight method, and their relative phonon densities of states were evaluated. The present results show that the phonon frequencies soften with the increase of the superconducting transition temperature Tc and harden with the decrease of the Tc, which is in agreement with our previous results of "The effect of Nb on phonons of superconductors C-15 V2Zr and V2(Zr0.5 Hf0.5)". This means that for these superconductors the elastic softening plays a role in enhancing Tc to some extent. It seems that between V2Zr or V2Hf and V2(Zr0.5 Hf0.5) there exists essential difference, which makes Tc increasing and the phonon frequencies softening for the formers while Tc decreasing and the phonon frequencies slightly hardening for the later after adding small amounts of Nb or Ta. It can be considered as the result of hybridzation of conduction bands, which is studied by means of the LMTO (linear combination of muffin-tin orbitals)method.

High order neutron components from Ge(lll) reflection have been measured in the region of 5—22 meV using time-of-flight method at the heavy water reactor in Beijing. The measured results have been compared with theoretical calculation and a satisfactory agreement is obtained. The results show that Ge(111) reflection suffers from a serious order contaminations below 20 meV.