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I got a pressure of 0 and Bulk Modulus expansion coefficients of B0=0.0811, B1=3.64 .
I’m just not sure what units they are in, does anyone know?
My guess would be p in GPa, B0 in GPa and no dimension for B1.I got a pressure of 22.58 GPa so I don’t think 0 is correct, bulk modulus was indeed in GPa (I got 1161 GPa) and I think B1 indeed doesn’t have a unit
From the Murnaghan equation, B_0 has units of pressure and B_1 is unitless. B_1 is unitless since derivative of a pressure with respect to pressure is unitless. Total energy values from QE are given in Ry, while lattice parameters are in Angstrom. So, some unit conversions are necessary to get B_0 in GPa. Your value of B_0 = 0.0811 is in Ry/Ang^3, so your value in GPa would be 177 GPa. I believe the expected is around 175 GPa.
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