Palliakaranai Thirumalai Narasimhan (1928–2013), popularly known as PTN or Jim, was an Indian theoretical chemist, one of the pioneers of computational chemistry in India and a professor at the Indian Institute of Technology, Kanpur. He was known for his studies on quantum-mechanical interpretation of magnetic resonance data and his contributions in developing IIT Kanpur into a Centre of Excellence in academic research in basic sciences. He was an elected fellow of the Indian National Science Academy, Indian Academy of Sciences and the National Academy of Sciences, India. The Council of Scientific and Industrial Research, the apex agency of the Government of India for scientific research, awarded him the Shanti Swarup Bhatnagar Prize for Science and Technology, one of the highest Indian science awards, in 1970, for his contributions to chemical sciences.
