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<p>Hi, </p>
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<p>I'm calculating the bulk modulus of different types of ice using ev.x.</p>
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<p>From the initial structure (.cif file) I increase and diminish the volume in around 7%. When the volume of .cif file is close to equilibrium volume, the calculation goes fine, with values of B0 and B0' close to experimental. </p>
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<p>But when the volume of .cif file is far from equilibrium volume, more than 7% range , B0 goes too high and B0' is usually low (~1).</p>
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<p>What is the right procedure to calculate the bulk modulus? </p>
<p>Should I vary volume until I find the lowest energy? Or should I always keep the range of around 7% from .cif file. </p>
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<p>Thank you in advance,</p>
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<p>Inna Nangoi</p>
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