  We present a review on the study of metastable silicon, primarily focusing
mainly on the aspects of liquid-liquid transition, critical point and phase
behaviour, structural and dynamic properties of liquid phase as well as crystal
nucleation. We begin with an extensive survey of the investigations of liquid
silicon pursued over three decades, with salient experimental, theoretical and
simulation results. Following which we present various scenarios put forward to
rationalize the density and related anomalies often observed in water and other
network forming liquids. After which we present the more recent investigations
(both simulation and experimental works) of the phase behavior of Silicon.
Since a significant part of metastable silicon work is on a classical empirical
potential an important question to address is the reliability of this potential
in describing the behavior of silicon. To provide a critical assessment of the
applicability of classical simulation results to real silicon we present a
comparison of the structural, dynamical, and thermodynamic quantities obtained
from the SW potential with those from ab initio simulations and with available
experimental data. We also discuss the sensitivity of the thermodynamic
properties to model parameters.
