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<p>Hey,<br>
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<p>I've tried to calculate the lattice parameter of silicon using the HSE hybrid in qe, however, when I do a number of scf simulations at various lattice parameters, the value I get which minimises the total energy is 10.22500 Ry, however, the stress value
for this simulation is actually extremely high, -5.44 kbar. Infact, I find that the lowest stress value is either 10.20 (1.60 kbar), this is still a high stress. Could anybody help explain this, or if they have encountered the same thing? Has the HSE been
properly implemented within espresso? <br>
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<div>Galvin,<br>
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<div>PhD student,<br>
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<div>University College London<br>
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