Effect of hydrostatic pressure on the magnetic and lattice properties of the ferromagnet La(Fe$_{0.86}$Si$_{0.14}$)$_{13}$

The temperature dependence of the lattice constant of the ferromagnet La(Fe$_{0.86}$Si$_{0.14}$)$_{13}$ has been measured at different pressures and temperatures. The numerical value of the bulk modulus at room temperature has been determined. The measurements of the temperature dependence of the lattice constant of the ferromagnet La(Fe$_{0.86}$Si$_{0.14}$)$_{13}$ at zero pressure and at 11.5 kbar have demonstrated that, at zero pressure, the lattice constant sharply decreases in the range from 160 to 210 K, whereas at a pressure of 11.5 kbar, the lattice constant decreases in the range from 110 to 180 K. This indicates that the Curie temperature $T_C$ changes from 210 to $\sim$ 170 K under pressure. The experimental results have been analyzed using the equations of states for the magnetic and elastic subsystems of the ferromagnet.