Recent experimental evidences have prompted us to study the dynamics of laser-assisted rotational excitation of a diatomic molecule due to an ion impact. The collision time between the ion and the molecule is very small (few atomic units) and the laser pulses considered are of picosecond range. We study the evolution of the rotational probabilities by varying the various laser parameters (pulse shape, field strength, pulse width, frequency) and collision parameters (impact parameter b, collisional velocity v). It is found that the probabilities of the rotational states depend strongly on the laser pulse parameters and the collision parameters. The study is more emphasised by studying ⟨J^{2}⟩ (a parameter defining the extent of the rotational excitation) and ⟨J_{z}⟩ for the system under concern. For higher value of b, the maximum value obtained by ⟨J^{2}⟩ increases and vice versa. Also, the molecule enters the transient mode for large b and v.
Zn_{0.95}Co_{0.05}O and Zn_{0.97}Ni_{0.03}O nanorods, prepared by a solvothermal method, show intriguing morphology and magnetic properties when co-doped with Li. At low and moderate Li incorporation (below 10 and 3 at.% Li in the Co- and Ni-doped samples, respectively) the rod aspect ratio is increased and room temperature ferromagnetic properties are enhanced, whereas the ferromagnetic coupling in Zn_{0.97}Ni_{0.03}O is decreased for Li concentrations < 3 at.%. First-principles theoretical analyses demonstrate that Li co-doping has primarily two effects in bulk Zn_{1- x}M_{x}O (with M = Co or Ni). First, the Li-on-Zn acceptors increase the local magnetic moment by depopulating the M 3d minority spin-states. The magnetic coupling is Ruderman-Kittel-Kasuya-Yosida-like both without and with Li co-doping. Second, Li-on-Zn prefer to be close to the M atoms to compensate the M-O bonds and to locally depopulate the 3d states, and this will help forming high aspect nanostructures. The observed room temperature ferromagnetism in Li co-doped Zn_{1- x}M_{x}O nanorods can therefore be explained by the better rod morphology in combination with ionizing the magnetic M atoms.
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