In this paper, taking Nb-Mo alloy system as an example, the equations of concentration of characteristic atoms of alloys in BCC structure were obtained on the basis of the idea of systematic science of alloys and the number of coordination atoms. The concentrations of characteristic atoms in B2-NbMo type ordered alloys were calculated as functions of ordering degree(s) and composition xMo. When s=smax, the concentrations of characteristic atoms of stoichiometric B2-NbMo intermetallic compound are equal to that of alloys, that is, Nb8Nb = 0.5 at., x0Mo = 0.5 at. As ordering degree decreases, characteristic atoms A8Nb and A0Mo of B2-NbMo type ordered alloy split. And the degree of splitting of characteristic atoms increases with the ordering degree decreasing. Therefore, disordered alloys and various types of ordered alloys can be designed.

Using the one-atom theory (OA) of pure metals, the atomic states of Ru metal with hcp structure, fcc structure, bcc structure and liquid state were determined as follows: [Kr](4dn)3.78(4dc)2.22(5sc)1.77(5sf)0.23, Ψa(fcc-Ru)=[Kr](4dn)3.70(4dc)2.44(5sc)1.42(5sf)0.44, Ψa(bcc-Ru)=[Kr](4dn)4.00(4dc)2.22(5sc)1.56(5sf)0.22, Ψa(L-Ru)=[Kr](4dn)4.00(4dc)2.00(5sc)1.52 (5sf)0.48. The potential curve and physical properties as a function of temperature for hcp-Ru such as lattice constant, cohesive energy, linear thermal expansion coefficient, specific heat and Gibbs energy and so on were calculated quantitatively. The theoretical results are in excellent agreement with experimental value. The relationship between the atomic states and catalytic performance was explained qualitatively and these supplied the designation of Ru metal and relative materials with theoretical instruction and complete data.