  Black hole thermodynamic stability can be determined by studying the nature
of heat capacity of the system. For Schwarzschild black hole the heat capacity
is negative, but in the quintessence field this system shows a second order
phase transition, implying the existence of a stable phase. We further discuss
the equation of state of the present system. While analyzing the quasinormal
modes, we find that the massive scalar quasinormal mode frequencies in the
complex $\omega$ plane shows a dramatic change when we plot it as a progressive
function of quintessence state parameter. We also find the Hawking temperature
of the system via the method of tunneling.
