The relative energy (a.u.) calculated with the ROHF/LANL2DZ method for Rh 8
clusters are shown in Table 2. We searched the spin multiplicity up to 21. The
relative energy of isomers with different geometry is 23.76, 1.023, and 1.249 eV for
the cubic, bctp, and incomplete-ico respectively. In Fig. 2, we show the optimized
structures of the Rh 8 clusters. Figure 2a is the lowest energy isomer, a bicapped
octahedron, bcoh, with a multiplicity equal to 19. Figure 2b corresponds to the
bicapped triangular prism isomer, bctp, with a multiplicity of 19. Figure 2c shows
an isomer with the incomplete icosahedron structure. Finally, a cubic isomer with
M = 13 is presented in Fig. 2d. The octahedron isomer with the minimum energy is
in complete agreement with the experimental results reported by D. J. Harding et al.
[10, 11], and by M. R. Beltran et al. [48], and with theoretical results obtained with
different methods such as local spin density [24, 57], molecular dynamics [26],
effective core potential [57], B3LYP [48, 49], which unlike of the reported here
Fig. 1 Isomers of Rh 6 geometry optimized with the B3LYP/MWB model chemistry, a tetrahedron, b triangular prism, c deformed pentagonal pyramid, d capped tetrahedron
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M. A. Mora and M. A. Mora-Ramírez
clusters are shown in Table 2. We searched the spin multiplicity up to 21. The
relative energy of isomers with different geometry is 23.76, 1.023, and 1.249 eV for
the cubic, bctp, and incomplete-ico respectively. In Fig. 2, we show the optimized
structures of the Rh 8 clusters. Figure 2a is the lowest energy isomer, a bicapped
octahedron, bcoh, with a multiplicity equal to 19. Figure 2b corresponds to the
bicapped triangular prism isomer, bctp, with a multiplicity of 19. Figure 2c shows
an isomer with the incomplete icosahedron structure. Finally, a cubic isomer with
M = 13 is presented in Fig. 2d. The octahedron isomer with the minimum energy is
in complete agreement with the experimental results reported by D. J. Harding et al.
[10, 11], and by M. R. Beltran et al. [48], and with theoretical results obtained with
different methods such as local spin density [24, 57], molecular dynamics [26],
effective core potential [57], B3LYP [48, 49], which unlike of the reported here
Fig. 1 Isomers of Rh 6 geometry optimized with the B3LYP/MWB model chemistry, a tetrahedron, b triangular prism, c deformed pentagonal pyramid, d capped tetrahedron
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M. A. Mora and M. A. Mora-Ramírez