Optical properties of chlorophosphate glasses of the type 50P2O5–30Na2HPO4–20RCl (R = potassium and lead) activated by 0×1 and 0×5 mol of Pr3+ and Nd3+ have been investigated. Optical band gaps (Eopt) have been reported for 0×1 and 0×5 mol concen

The External Force matrix, F, contains the magnitude of all externally % applied loads, (input as e1, e2, e3 components), stored in the % proper rows to corespond with the node it is applied at.