Seminar DMONS – DCMI – Axis 5 presented by : Abhishake MONDAL

Abhishake MONDAL (Solid State and Structural Chemistry Unit, Indian Institute of Science, Bangalore)

Abstract : 

The pursuit of smart multifunctional materials with stimuli-responsive magnetic and optical response has drawn escalating interest in both fundamental science and potential applications to switches, sensors, and intelligent devices.1 One of the appealing feature of such materials is the tunability of their physical property via chemistry, where the linking structure and physical properties can be modulated in practically infinite ways, which gives them an edge over the solid-state magnetic materials (Figure 1, a).2 The field of molecular bistable systems is rapidly budding towards utilizing these molecule-based magnetic materials in physics-driven and nanotechnology-driven fields (Figure 1, b).

Figure 1: a) Stimuli-responsive molecular bistable systems and b) Application areas where these systems are actively studied for developing devices

Here, I will briefly cover the exciting field of Molecular Magnetism and will specifically focus on three most important aspects of Molecular Magnetism being pursued in my laboratory i) Spin Crossover (SCO) materials3 ii) Metal-to-Metal Electron Transfer Systems (MMET)4 and iii) Single Molecule Magnets (SMM).5 Lastly, I shall discuss the application of these bistable systems in developing ring-resonator devices for Photonics Application, molecular break junctions and microelectromechanical systems.

Acknowledgments: I thank the Indian Institute of Science (IISc), Bangalore, India, and the Ministry of Human Resource Development (MHRD), Ministry of Education (MoE), Government of India, IISc-Start-up Research Grant, the Department of Science and Technology, Mission on Nano Science and Technology (Nano Mission), Scheme for Transformational and Advanced Research in Sciences (STARS, MHRD), Council of Scientific and Industrial Research (CSIR) for the research fundings.

References:

1. Kamilya, S.; Dey, B.; Kaushik, K.; Shukla, S.; Mehta, S.; Mondal, A. Chem. Mater. 2024, 36, 4889, Kaushik, K.; Mehta, S.; Das, M.; Ghosh, S.; Kamilya, S.; Mondal, A., Chem. Commun., 2023, 59, 13107, Coronado, E., Nat. Rev. Mater. 2020, 5, 87. 2. Minguez Espallargas, G.; Coronado, E., Chem. Soc. Rev. 2018, 47, 533. 3. Ghosh, S.; Kamilya, S.; Pramanik, T.; Rouzieres, M.; Herchel, R.; Mehta, S.; Mondal, A., Inorg. Chem. 2020, 59, 13009, Ghosh, S.; Ghosh, S.; Kamilya, S.; Mandal, S.; Mehta, S.; Mondal, A., Inorg. Chem. 2022, 61, 17080, Bagchi, S.; Kamilya, S.; Mehta, S.; Mandal, S.; Bandyopadhyay, A.; Narayan, A.; Ghosh, S.; Mondal, A., Dalton Trans., 2023, 52, 11335, Ghosh, S.; Bagchi, S.; Kamilya, S.; Mehta, S.; Sarkar, D.; Herchel R.; Mondal, A., Dalton Trans., 2022, 51, 7681. 4. Kamilya, S.; Ghosh, S.; Li, Y.; Dechambenoit, P.; Rouzières, M.; Lescouëzec, R.; Mehta, S.; Mondal, A., Inorg. Chem., 2020, 59, 11879, Kamilya, S.; Ghosh, S.; Mehta, S.; Mondal, A., J. Phys. Chem. A 2021, 125, 4775. 5. Hossain, S. M.; Kamilya, S.; Ghosh, S.; Herchel, R.; Kiskin, M. A.; Mehta, S.; Mondal, A., Cryst. Growth Des. 2023, 23, 1656.

Seminar DCMI and Axes 3 and 5 : presenetd by Raquel UTRERA MELERO

Abstract : Materials exhibiting luminescence stimuli-responsive properties, present potential application as detection systems. Among these materials, copper (I) iodide molecular clusters coordinated by phosphine ligands, exhibit thermochromic and mechanochromic luminescence properties. These compounds are characterized by a change of their emission wavelength in response to temperature or mechanical stress. The establishment of structure- properties relationships permit to study the mechanisms responsible for their properties. The main characterization techniques used are solid-state NMR, X-ray diffraction, Infrared and Raman spectroscopies. In addition to the thermo and mechanochromic properties, these compounds have the particularity of exhibiting aggregation-induced emission (AIE) properties. The understanding of properties is crucial for applications. Therefore, DFT (Density Functional Theory) calculations are also carried out to rationalize the different results and in particular the optical properties. In the last years, copper has been proposed as a substituent in lead perovskite-based devices due to its non-toxic nature. We are currently investigating the use of copper perovskites for solar cells.

PhD defense : Steve Dave WANSI WENDJI

The defense will be held on Friday, September 20, 2024 at 9:25 a.m. in the Grünewald amphitheater of the IPHC (building 25, Cronenbourg campus).

The work was carried out under the supervision of Carlo MASSOBRIO (MATISEN – ICube) and Guido ORI (DCMI-IPCMS).

PhD Defense : Xavier Henning

Xavier Henning (IPCMS / DMO-DCMI)

This work was carried out under the supervision of Dr. Mircea RASTEI (DMO) and Prof. Aziz DINIA (DCMI).

HDR Defense : Guido ORI

The defense will be held in english and will take place on Wednesday (June 19th) at 14:30 h in the Auditorium of IPCMS (Campus Cronenbourg).

Seminar DCMI and Axis 4 and 5, presented by Paul STEADMAN

Speaker: Paul STEADMAN (Responsable de la ligne I10 au Synchroton Diamond)

Abstract : A study of the electric current induced hysteresis in Pt/CoFeTaB thin films revealed an unexpected behaviour in the hysteresis curves measured using polarised soft X-ray reflectivity [1]. Following a detailed study of the polarisation dependence of the reflected intensity [2] both detailed calculations and experimental data revealed that the switching is Y type (magnetisation switching perpendicular to the current), is very sensitive to external magnetic fields and that, rather bizarrely, only part of the film is switching. In addition the importance of non-linear dependence on the magnetic scattering and its dependence on polarisation and energy have been uncovered experimentally and explained with a very simple model.

  • [1] D. M. Burn, R. Fan, O. Inyang, M. Tokac¸ L. Bouchenoire, A. T. Hindmarch and P. Steadman, P. (2022). Phys. Rev. B, 106, 094429.
  • [2] Raymond Fan, Kiranjot, Razan O. M. Aboljadayel, Kalel Alsaeed, Peter, J. Synchrotron Rad. (2024). 31, 493–507

PhD Defense : Mohammed GUERBOUB

These works were carried out under the supervision of  Mr. Carlo MASSOBRIO and Mr. Guido ORI at IPCMS in the DCMI department.

The defense will take place in English on Wednesday, December 13th, 2023 at 14:00  in the IPCMS auditorium.