Thus, the vibrational excitations are accompanying the electron transitions of the molecule. Figure 3 Bias voltage dependence of the vibrational occupation number and the population of the molecular exciton. Red solid and green

dashed lines refer to the vibrational occupation number for vibrational state in nonequilibrium and thermal equilibrium, respectively. The blue dashed-dotted line refers to the population of the molecular exciton. Here, (a, b) T pl = 10-4 and , (c, d) T pl = 10-2 and , (e, f) T pl = 10-4 and , and (g, h) T pl = 10-2 and . The exciton-plasmon coupling is V = 0.10 eV. To analyze the mechanism for the occurrence of the electron transitions accompanied by the vibrational MDV3100 cost excitations at , the spectral

function of the molecule A L is shown in Figure 4. Due to the exciton-plasmon coupling V, the position and the width of the peaks in A L are shifted and broadened, respectively. The spectral intensities are found in the energy range lower than . It indicates that the excitation channels of the molecule arise in this energy range. Thus, the electron transitions of the molecule occur via the excitation channels resulting from the check details exciton-plasmon coupling and give rise to the vibrational excitations. Figure 4 Spectral functions of the molecule for ( a ) V = 0.0 eV and (b to e) V = 0.1 eV . The bias voltage is V bias = 1.8 V. Here, (b) T pl = 10-4 and , (c) T pl = 10-2 and , (d) T pl = 10-4 and , and (e) T pl = 10-2 and . Conclusion The exciton-plasmon coupling has a strong influence on the luminescence property of the molecule. The excitation channels of the Org 27569 molecule arise even in the energy range lower than the HOMO-LUMO gap energy . It is found that the electron transitions of the molecule via these excitation channels give rise to the molecular luminescence and the vibrational excitations at the bias voltage . Our results also indicate that the vibrational excitations assist the occurrence of the upconverted luminescence.

Acknowledgements This work is supported in part by MEXT (Ministry of Education, Culture, Sports, Science and Technology) through the G-COE (Special Coordination Funds for the Global Center of Excellence) program ‘Atomically Controlled Fabrication Technology’, Grant-in-Aid for Scientific Research on Innovative Areas Program (2203-22104008), and Scientific Research (c) Program (22510107). It was also supported in part by JST (Japan Science and MK 8931 ic50 Technology Agency) through the ALCA (Advanced Low Carbon Technology Research and Development) Program ‘Development of Novel Metal-Air Secondary Battery Based on Fast Oxide Ion Conductor Nano Thickness Film’ and the Strategic Japanese-Croatian Cooperative Program on Materials Science ‘Theoretical modeling and simulations of the structural, electronic and dynamical properties of surfaces and nanostructures in materials science research’.