## Design of fullerene and metal-diothiolene-based materials for photonic applications

The overall project on which we are working involves the **design of** **fullerene and M- dithiolene-based** **materials**, where M=Ni, Pd etc, for photonic applications. The key parameters for such a design are the nonlinear optical (NLO) properties. The increasing demand for faster data processing, storage and distribution can only be fulfilled by ongoing miniaturisation of the basic electronic devices. The traditional silicon-based technologies used nowadays are approaching intrinsic limits in this respect, and new approaches are needed. Photonic technology, where light is used as information carrier instead of electrons, is considered to offer the answer. An important step towards this goal is the development of new photonic materials with large NLO properties by employing nano-derivatives.

The basic concept on which the project is based involves first, the design of novel dyads employing fullerenes and metal-dithiolenes for photonic applications and second, the solution of several methodological problems, which are of current interest in this area and which are instrumental for the reliable computation of reliable L&NLO properties of the proposed derivatives.

The computations are extremely resource consuming, because one needs highly accurate energy values, since for example, the second hyperpolaizability is a fourth order derivative of the field dependent energy with respect to the field. The reliability of the computed results is directly related with the accuracy of the relevant energy and property derivatives. For this purpose the Romberg fitting procedure is employed, which requires a number of computed energies or property values, evaluated by using a number of steps of magnitude 2kQ, where k=0,1,2,… and Q=0.01 a.u. Usually for the evaluation of the derivatives we use 6-10 points.

There is currently a great interest in the optical properties of nano-structures due to requirements for materials that allow very high bit-rate in long-distance optical communication. Many devices require materials with NLO figures of merit several orders of magnitude higher than those of materials currently in use. Derivatives with large NLO properties and fast response, such as fullerene-based nano-materials are required for a large number of applications (e.g. fiber optic communication, all optical switching, optical storage media etc). Thus our approach, which includes some state-of-the-art theoretical techniques is expected to lead to some novel and useful photonic nano-materials.

**Application's name:** Design of fullerene and metal-diothiolene-based materials for photonic applications

**Scientific contact**: Manthos G. Papadopoulos (mpapad at eie.gr)

**Technical contact**: Heribert Reis (hreis at eie.gr)

**Developers**: Computational Chemistry Group of NHRF, Greece

**Web site**:http://www.eie.gr/nhrf/institutes/iopc/cvs/cv-papadopoulos-gr.html

For more information visit HP-SEE Wiki page.

**Scientific papers**:

- B. Skwara, R. G. Gora, R. Zalesny, P. Lipkowski, W. Bartkowiak, H. Reis, M. G. Papadopoulos

**"Electronic Structure, Bonding, Spectra, and Linear and Nonlinear Electric Properties of [email protected]**_{28}"

J. Phys. Chem. A, 2011, 115 (37), pp 10370–10381

DOI: 10.1021/jp206331n - A. Avramopoulos, J. Li, N. Holzmann, G. Frenking, M. G. Papadopoulos

**"On the Stability, Electronic Structure, and Nonlinear Optical Properties of HXeOXeF and FXeOXeF"**

J Phys. Chem A, 2011, 115 (36), pp 10226–10236

DOI: 10.1021/jp203961k