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    Well, maybe because in your first calculation you had two atoms, and
    64 in the second one.....You should try to see if multiplying
    -107.10 by 64/2 improve the comparison....<br>
    <br>
    L. <br>
    <br>
    <div class="moz-cite-prefix">On 16/01/2020 06:23, Pooja Vyas wrote:<br>
    </div>
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cite="mid:CAKPq2FF7Dto1bx9PdEr71X5J18L4oCQtL9nn_CH1UNAPryL3PQ@mail.gmail.com">
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        <div>Initially I had run my input script with ecut=100Ry and
          k-points= 11 11 11 1 1 1. At that time my energy was
          -107.10Ry. During this run, I had specified only two atomic
          positions (Ca: 0 0 0, O: 0.5 0.5 0.5)<br>
        </div>
        <div>For the same system but with ecut=60Ry and k-points= 3 3 3
          1 1 1 the calculated energy was -3427.40Ry. During this run, I
          had specified 64 atomic positions.</div>
        <div>Why does total energy value vary so much?<br>
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    <br>
    <pre class="moz-signature" cols="72">-- 
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