Database of Quantum Self-Capacitance of Molecules (QSCM)
　
Quantum capacitance is an important physical quantity that governs the electronic transport properties, in particular of nanometer-scale objects. In this database, QSCM, we provide the data of self-capacitances of several kinds of molecules that have been determined by the Density-Functional Theory (DFT) calculations. [1-3] The self-capacitance  is defined by [4-5]

.

Here,  is an electron charge and  is the ground-state total energy of a system with electrons.  The self-capacitance, i.e., twice the capacitance of bielectrodes with an infinite gap, shows remarkable quantum effects that are attributed to the discrete electronic levels of nano-scale electrodes or molecules.

 Please refer to the references [1-3] when you use the database, QSCM in your presentations and/or publications.





Acknowledgements:

The database QSCM was created by a program code, the Quantum Capacitance Simulator (QCAPS) that has been developed through a financial support from the Japan Science and Technology Corporation (JST-CREST). The GUI of the database QSCM was made thanks to financial support from the "Academic Frontier" Project of the Ministry of Education, Culture, Sports, Science and Technology of Japan through Holistic Computational Science (HOLCS) of Tokyo University of Science.




References:

[1] N. Nakaoka, K. Watanabe; Eur. Phys. J. D 24, 397 (2003).
[2] N. Nakaoka, K. Watanabe; Thin Solid Films 464-465, 346 (2004).
[3] K. Watanabe, S. Watanabe, M. Tanaka, N. Nakaoka; Jpn. J. Appl. Phys. 44, 5348 (2005).
[4] G. J. Iafrate, K. Hess, J. B. Krieger, M. Macucci; Phys. Rev. B 52, 10737 (1995).
[5] V. Ranjan, R. K. Pandey, M. K. Harbola, V. A. Singh; Phys. Rev. 65, 045311 (2002)