Insights into modeling refractive index of ionic liquids using chemical structure-based machine learning methods Ali Esmaeili, Hesamedin Hekmatmehr, Saeid Atashrouz, Seyed Ali Madani, Maryam Pourmahdi, Dragutin Nedeljkovic, Abdolhossein Hemmati-Sarapardeh & Ahmad Mohaddespour Journal of  Scientific Reports