<html dir=""><head><style id="axi-htmleditor-style" type="text/css">p { margin: 0px; }</style></head><body style="font-size: 10pt; font-family: Arial; background-image: none; background-repeat: repeat; background-attachment: fixed;">​dear users<br> <br>I am trying to optimize structural properties of an alloy which is doped. This compound has 4 free parameters ( one lattice parameter + three internal free parameter). Now how can i find best optimize state for these parameter. Is there any method to simultaneously optimized energy in terms of these free parameters. <br><br>thank you in advance <br></body></html>