Pressure-induced coherent sliding-layer transition in the excitonic insulator Ta2NiSe5

Nakano, A.; Sugawara, K.; Tamura, S.; Katayama, N.; Matsubayashi, K.; Okada, T.; Uwatoko, Y.; Munakata, K.; Nakao, A.; Sagayama, H.; Kumai, R.; Sugimoto, K.; Maejima, N.; Machida, A.; Watanuki, T.; Sawa, H.

doi:10.1107/S2052252517018334

Figure 5
(a) Pressure dependence of the interlayer Se(1)–Se(3) (blue) and Se(2)–Se(3) (red) distances as determined by both single-crystal (empty circles) and powder (filled circles) XRD measurements. Se(1)–Se(3) represent three different crystallographic sites (as represented in Figs. 3

d, 4

a and 4

c). (b) Pressure dependence of the cluster volume of a Ta–Se octahedron (violet) and an Ni–Se tetrahedron (green). In each case, the empty and filled symbols represent the results of the single-crystal and powder XRD measurements, respectively. The blue, red, violet and green solid lines are guides for the eye. The experimental data points from a previous report at 0 GPa (Sunshine & Ibers, 1985