MS22-P04 Influence of chosen synthons on the polarizabilities of functional groups Anna Krawczuk (Faculty of Chemistry, Jagiellonian University in Krakow, Krakow, Poland) Marcin Kaczmarczyk (Faculty of Chemistry, Jagiellonian University in Krakow, Krakow, Poland)email: krawczuk@chemia.uj.edu.plThe correlation between the crystal structure and physical properties of a given material has long been a subject of many studies. One of the key features of designing efficient multifunctional materials is to use specific building blocks and/or synthons in order to increase a desired effect in the certain crystallographic direction. For example, to obtain efficient optical devices it is necessary to use highly polarizable functional groups which will promote high optical effect. It is thus crucial to get a precise information on how those group polarizabilities are influenced by common synthons used in crystal engineering. 
Recently developed routine, PolaBer [1] allows to calculate atomic polarizabilities, and therefore group polarizabilities, based on the definition of atomic dipole moments given by Bader [2]. The routine uses the results of QTAIM partitioning of electron densities. According to QTAIM theory each atomic contribution can be expressed as a sum of atomic polarization and charge translation terms. The numerical derivatives of these quantities with respect to external electric field provide atomic and group polarizabilities. The advantage of using group polarizabilities rather than molecular ones, is the fact that we can extract separate information about the functional group and intermolecular contribution into linear susceptibility. This, on the other hand, enables to identify which group mostly contributes to the global dielectric constant, thus could be very helpful in reverse crystal engineering [3] purpose when designing new optically effective materials.
 
References:

[1] Krawczuk A., PĂ©rez D., Macchi P. (2014). J. Appl. Cryst. 47, 1452-1458.

[2] Bader R.F.W. Atoms in Molecules: A Quantum Theory, Oxford University Press, Oxford, U.K., 1990.

[3] Macchi P. (2014) Chimia 68, 31-37.
Keywords: group polarizability, synthons, optical properties