Dear yuehua<br>i think your forc_conv_thr=1.D-6 is too tight for your calculation ..<br>Usually, For most calculation 1.D-4 is very fine..<br><br><div><span class="gmail_quote">On 7/13/07, <b class="gmail_sendername">xu yuehua
</b> <<a href="mailto:njuxuyuehua@gmail.com">njuxuyuehua@gmail.com</a>> wrote:</span><blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;"><div>
hello all</div>
<div>i am doing relax.</div>
<div>in my inputfile,</div>
<div>i use etot_conv_thr=1.D-6<br> forc_conv_thr=1.D-6</div>
<div>and the output is </div>
<div> atom 1 type 1 force = 0.00000290 0.00000095 -0.00000364<br> atom 2 type 1 force = 0.00000081 -0.00000108 0.00000033<br> atom 3 type 1 force = -0.00000435 -0.00000425 -
0.00000160<br> atom 4 type 1 force = -0.00000312 -0.00000321 -0.00000080<br> atom 5 type 1 force = -0.00000446 -0.00000036 -0.00000273<br> atom 6 type 1 force = -0.00000048
0.00000230
0.00000112<br> atom 7 type 1 force = 0.00000164 0.00000118 0.00000060<br> atom 8 type 1 force = 0.00000131 -0.00000040 0.00000145<br> atom 9 type 2 force = -0.00000362
0.00000154 -0.00000201<br> atom 10 type 2 force = -0.00000029 0.00000191 0.00000302<br> atom 11 type 2 force = 0.00000576 -0.00000134 0.00000194<br> atom 12 type 2 force =
0.00000390
0.00000276 0.00000233<br><br clear="all"></div>
<p>Total force = 0.000015 Total SCF correction = 0.000054<br> <font color="#ff6666">SCF correction compared to forces is too large, reduce conv_thr</font></p>
<p> The maximum number of steps has been reached.</p>
<div>my qustion is ,force at every atom is ok ,but why the program asks to reduce conv_thr</div>
<div>my conv_thr is not enough small ?</div>
<div>or my total relax step (50) is not adequate?</div>
<div>is there any principle about these parameter?</div>
<div>need your help</div>
<div>thanks a lot <br>-- <br>Xu Yuehua<br>physics Department of Nanjing university<br>China </div>
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<br><br clear="all"><br>-- <br>Hai-Ping Lan <br>Department of Electronics ,<br>Peking University , Bejing, 100871<br><a href="mailto:lanhaiping@gmail.com">lanhaiping@gmail.com</a>, <a href="mailto:hplan@pku.edu.cn">hplan@pku.edu.cn
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