Institution: | 1.Centre of Excellence in Solid State Physics, University of the Punjab, Quaid-e-Azam Campus, Lahore-54590, Pakistan2.Physics and Astronomy Department, College of Science, King Saud University, P. O. Box 2455, Riyadh 11451, Saudi Arabia3.Chemical Engineering Department, College of Engineering, King Saud University, P. O. Box 800, Riyadh 11421, Saudi Arabia |