<div dir="ltr"><p style="margin:0px 0px 10px;color:rgb(51,51,51);font-family:roboto,arial,sans-serif;font-size:14px">I am new to WIEN2k. I am in need for help from the experts in finding the elastic constants.</p><p style="margin:0px 0px 10px;color:rgb(51,51,51);font-family:roboto,arial,sans-serif;font-size:14px">I am interested in finding out the elastic constants of trigonal systems by WIEN2k.</p><p style="margin:0px;color:rgb(51,51,51);font-family:roboto,arial,sans-serif;font-size:14px">There are packages available for hexagonal, tetragonal, orthorhombic and cubic systems. What should I do for Trigonal systems.</p><p style="margin:0px;color:rgb(51,51,51);font-family:roboto,arial,sans-serif;font-size:14px"><br></p><p style="margin:0px;color:rgb(51,51,51);font-family:roboto,arial,sans-serif;font-size:14px">I have used the hexagonal package but I have obtained quite large values for one constant and very large negative values for another.</p><p style="margin:0px;color:rgb(51,51,51);font-family:roboto,arial,sans-serif;font-size:14px">One of the plot also shows oscillations and it is not correct.</p><p style="margin:0px;color:rgb(51,51,51);font-family:roboto,arial,sans-serif;font-size:14px">Kindly guide me.</p><p style="margin:0px;color:rgb(51,51,51);font-family:roboto,arial,sans-serif;font-size:14px"><br></p><p style="margin:0px;color:rgb(51,51,51);font-family:roboto,arial,sans-serif;font-size:14px">Regards</p><p style="margin:0px;color:rgb(51,51,51);font-family:roboto,arial,sans-serif;font-size:14px">Yasir Javed</p><p style="margin:0px;color:rgb(51,51,51);font-family:roboto,arial,sans-serif;font-size:14px">Department of Metallurgy and Materials Engineering (DMME),</p><p style="margin:0px;color:rgb(51,51,51);font-family:roboto,arial,sans-serif;font-size:14px">Pakistan Institute of Engineering and Applied Sciences (PIEAS)</p><p style="margin:0px;color:rgb(51,51,51);font-family:roboto,arial,sans-serif;font-size:14px">Pakistan</p></div>