Figure 6
On a plot of c/a versus RA/RB, the MoSi2-type compounds form two groups. AlCr2, AlTc2 and MoU2 (blue open circles) which were exceptions in Fig. 5[link] are exceptions in this figure too. The compounds with [\Delta\varphi] = [{\varphi}_{A}] - [{\varphi}_{B}] positive (blue squares) have higher c/a values and have RA/RB values less than 1.0. The direction of charge transfer (Pauling, 1950BB27) is appropriate to shift the radius ratio of the atoms to 1.0 in the structure. The compounds with [\Delta\varphi] = [{\varphi}_{A}] - [{\varphi}_{B}] negative (red open circles) have lower c/a values and have RA/RB values greater than 1.0. The direction of charge transfer is appropriate to shift the radius ratio of the atoms to 1.0 in the structure.  [article HTML]

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