  The spectroscopic properties of Li atom and Li-like Ca and Ti ions in the
plasma environment are investigated using a relativistic coupled-cluster (RCC)
method. Assuming the plasma is of low density and very hot, we consider the
Debye model with two approximations by accounting the screening effects: (i) in
the nuclear potential alone and (ii) in both the nuclear and the
electron-electron interaction potentials. First, the calculations for the
energies and the lifetimes of the atomic states are carried out for the plasma
free systems in order to check their accuracies following which they are
investigated in the plasma environment. It is observed that screenings in the
electron-electron interaction potentials stabilize the systems more than the
case when the screenings present only in the nuclear potential. Similarly, the
earlier predicted blue and red shifts in the $\Delta n=0$ and $\Delta n \ne 0$
transition lines (with the principal quantum number $n$) of the Li-like ions
change significantly in the case (ii) approximation. The level-crossings among
the energy levels are observed for the large screening effects which seem to be
prominent in the states of higher orbital angular momentum. The lifetimes of
many low-lying states and the relative line-intensities of the allowed
transitions are estimated considering different plasma screening strengths.
