[1] Vikram Univ, Sch Studies Phys, Ujjain 452001, Madhya Pradesh, India
[2] Govt PG Coll, Rajgrah 465611, India
[3] Univ Allahabad, Dept Chem, Allahabad 211002, Uttar Pradesh, India
[4] Bhabha Atom Res Ctr, Appl Spectroscopy Div, Bombay 400085, Maharashtra, India