Revision # 2 1 Density Functional investigation of the thermo-physical and 2 thermochemical properties of 2 M 1 Muscovite 3

Revision #2 1 Density Functional investigation of the thermo-physical and 2 thermo-chemical properties of 2M1 Muscovite 3 Gianfranco Ulian and Giovanni Valdrè* 4 5 Centro di Ricerca Interdisciplinare di Biomineralogia, Cristallografia e Biomateriali, Dipartimento 6 di Scienze Biologiche, Geologiche e Ambientali, Università degli Studi di Bologna, Piazza di Porta 7 San Donato 1, 40126 Bologna, Italy 8 E-mail: giovanni.valdre@unibo.it, Phone: +39-051-2094943, Fax: +39-051-2094943 9 10 11 Abstract 12 In the present study, we computed the thermo-chemical and thermo-physical properties of the 2M1 13 polytype of muscovite in the 0 – 10 GPa and 0 – 900 K ranges, using the hybrid DFT/B3LYP-D* 14 density functional, corrected to take into account dispersive forces, and by using the quasi-harmonic 15 approximation. The bulk modulus KT0 of muscovite, its first derivative K’ and the unit-cell volume 16 at zero pressure V0 at 298.15 K, calculated using a third-order Birch-Murnaghan equation of state, 17 were KT0 = 59.93 GPa, K’ = 7.84 and V0 = 940.6 Å. Our theoretical data are in good agreement 18 with previous experimental results obtained by X-ray diffraction. Thermal bulk moduli, KT, thermal 19