Nirmalangshu Chakraborty, featured ILCC liquid crystal artist, May 2016
Nirmalangshu Chakraborty was UGC research fellow at Assam University, Silchar, India. He completed his Ph D programme with Prof Nandiraju V S Rao, Department of Chemistry, Assam University, Silchar, India related to the design, synthesis and characterization of achiral four-ring bent-core compounds and influence of substituents on the mesomorphism of these four ring compounds and to study their optical properties. Dr Chakraborty visited Tokyo Institute of Technology, Tokyo, Japan as Research Fellow under Global COE programme of Education and Research Centre for Material Innovation and advanced studies related to chirality in achiral liquid crystals and optical characteristics in novel nematic phases under the guidance of Prof. Ken Ishikawa and Prof. Hideo Takezoe in the Department of Organic and Polymeric Materials, Tokyo Institute of Technology, Japan. Then after he worked as post doctoral fellow with Prof. N Jayaraman in the Department of Organic Chemistry, Indian Institute of Science, Bangalore, India in the field of dendrimer liquid crystals and nano objects coming from dendromesogens.
He has been awarded by DST-SERB as a Young Scientist and now working with Dr. A. S. Achalkumar, Associate Professor, Department of Chemistry, Indian Institute of Technology Guwahati, India in the field of Luminescent metallomesogens for organic light-emitting diodes.
His research interest lies in the synthesis and studies of electric-field responsive liquid crystals, chiral nematic liquid crystals, blue phases, polarization modulated B7 phases for the design of electro-optical materials.
The image resembles toroid like textures with schlieren defects which was taken in a commercial polyimide coated parallel rubbed sandwich cell of approximately 5.0 μm. These droplets further transformed into optical textures resembling the tactoid textures observed in nematic lyotropic chromonic liquid crystals formed by nontrivial shaped systems. The tactoid textures grow in size upon prolonged cooling but never transformed into total extinction of the sample or even on decreasing the temperature. These optical textures are found to grow through a process of nucleation, growth and coalescence over a period of time of few hours depending on the thickness of the sample. During the growth process neighbouring tactoids are seen to coalesce into a single tactoid. The picture was taken at 118oC on Nikon Polarizing microscope attached with Instec STC 200 hot stage and Nikon Digital sight DS-Fi1 digital camera.