Structure Etot (eV) EA (eV) IP (eV) Eg(eV) µ Cv Si14oa -69.58 2.61 6.76 1.30 1.03 71.38 Si14ob -69.35 2.61 6.94 1.40 1.20 72.00 Si14oc -69.34 2.48 7.00 1.69 1.02 71.98 Si15oa -74.90 1.60 8.11 1.85 2.37 76.92 Si15ob -74.17 2.66 7.11 1.56 0.42 76.51 Si15oc -74.06 2.44 7.23 1.78 2.19 76.74 Si16oa -78.72 2.86 6.58 0.94 0.84 80.73 Si16ob -78.65 2.78 6.48 0.72 1.27 80.99 Si16oc -78.49 2.81 6.68 0.92 0.91 80.87 Si17oa -83.45 3.05 7.13 1.21 0.72 86.54 Si17ob -83.44 2.90 6.86 1.27 0.12 86.72 Si17oc -83.06 2.63 6.53 1.08 1.55 86.85 Si18oa -87.61 2.51 6.79 2.03 3.25 92.28 Si18ob -87.58 2.50 6.72 1.54 4.47 91.64 Si18oc -87.54 3.08 7.01 1.05 1.96 93.21

Table 1: The total binding energy (Etot, in eV), electron affinity (EA, in eV), ionization potential (IP, in eV), the gap of HOMO-LOMO (Eg, in eV), dipole moment (µ, in Debye), and total constant volume heat capacity (Cv(tot), in cal/mol K), for the three lowest energy structures of SinO (n=14-18) clusters.