**5. Acknowledgment**

18 Molecular Dynamics – Theoretical Developments and Applications in Nanotechnology and Energy

dipole moment of *trans*-platin is much smaller than that of *cis*-platin. This means that the number of water molecules which coordinates to the platin complex is larger for *cis*-platin than for *trans*-platin. Thus, the CT interaction coupled with the solvent motion is stronger in *cis*-platin than in *trans*-platin. As a result, the Pt-Cl bonds are easier to elongate for the cleavage in the hydrated *cis*-platin than in the hydrated *trans*-platin. Thus, by using FMO-MD simulations, we obtained new quantum chemical insight into the solvation of platin

 Fig. 12. (Left) Time evolution of natural charge on the Pt, NH3, and Cl sites in the *cis*- and *trans*-platin. Solid and dotted lines indicate *cis*- and *trans*- isomers, respectively. (Right) Time

As reviewed so far, FMO-MD has been applied to various chemical phenomena in the presence of explicit solvents and has given realistic molecular pictures of the phenomena. We are planning to extend the field of FMO-MD by introduction of new capabilities, as

The so-called QM/MM scheme will enhance the target size of FMO-MD. QM/MM has attracted great interest in simulating condensed-phase systems as well as proteins. In this scheme, the chemically relevant region is subjected to QM calculations while the environmental effects are incorporated through a set of MM parameters. MFMO has a conceptual similarity to QM/MM, and hence we have a plan to implement a general

The improvement of accuracy in FMO gradient evaluations may be a future subject. Nagata's reformulation, including the supplemental response terms of monomers (Nagata *et al.*, 2011a) as well as the BDA-related residual contributions (Nagata *et al.,* 2010), are of

Another important issue is the extraction of more information from FMO-MD trajectories. From a series of configurations, the time-dependent fluctuations in electronic densities can be derived, some of which are correlated with the creation and destruction of bonding interactions. For example, the Fourier transform-based analyses may shed light on the

evolution of Pt-Cl bond lengths. Reproduced from Mori *et al.* (2012) by permission.

complexes.

follows.

**4. Prospects and conclusion** 

QM/MM ability in conjunction with MFMO.

interest for implementation at the HF level.

detailed dynamical picture of nucleophilic attack reactions.

Thanks are due to Dr. Makoto Sato, Mr. Takayuki Fujiwara, Mr. Yuji Kato, and Professor Hiroshi Yamataka of Rikkyo University, Dr. Yoshio Okiyama of Tokyo University, Ms. Natsumi Hirayama of Ochanomizu University, Professor Takeshi Ishikawa of Gifu University, and Dr. Takatoshi Fujita and Professor Shigenori Tanaka of Kobe University for their collaboration in the FMO-MD project. The works presented in this articles have been supported by the following funds: the Core Research for Evolutional Science and Technology (CREST) project of the Japan Science and Technology Agency (JST) to YK, YM, TK, and HM; the Grant-in-Aid for Scientific Research from the Ministry of Education, Culture, Sports, Science and Technology of Japan (MEXT) to YM ("Molecular Theory for Real Systems") and to YM and YK ("Molecular-level analyses of dynamics-controlled organic reactions"); the Ocha-dai Academic Production project by JST, Funding from Sumitomo Foundation, and Advanced Scientific Computing project 2010 at the Research Institute for Information Technology of Kyushu University to HM; the Rikkyo University Special Fund for Research (SFR) to YM, YK, and HM; and the Research and Development of Innovative Simulation Software (RISS) project at the Institute of Industrial Science of the University of Tokyo to TN and YM. Some of the calculations were performed using computing resources at the Research Centre for Computational Science, Okazaki, Japan.
