Quantum-classical dynamics of the capture of neon atoms by superfluid helium nanodroplets

Abstract

The capture dynamics of Ne by a HeND was studied theoretically in a detailed manner (energy and angular momentum transfer and vortex formation).

Quantum dynamics of the Br2 (B-excited state) photodissociation in superfluid helium nanodroplets: importance of the recombination process

“…In this method, which has been previously proposed by us and applied to the related Cl 2 case, 25,26 the helium atoms are described by means of the mean field TDDFT method and the molecule is described using a time dependent quantum wave packet (WP). Besides, the common so-called Orsay-Trento (OT) phenomenological density functional (T = 0 K) 42 , including some reasonable and commonly used approximations (the backflow term and the non-local contribution to the helium correlation energy have not been considered), [25][26][27][29][30][31][32][33][34][35][43][44][45] has been used to account for the helium.…”

“…This work has been carried out employing a quantum hybrid method proposed 25 and previously applied by us (with some modifications when needed) to investigate the dynamics of several physicochemical problems involving ( 4 He) N and atoms or diatomic molecules (photodissociation, [25][26][27] atom capture, 28,29 van der Waals reaction, 30,31 vibrational relaxation, 32,33 rotational relaxation 34 and helium nanodroplet relaxation 35 ). Therefore, time dependent density functional theory (TDDFT) and standard quantum mechanics have been used to describe helium and the Br 2 molecule, respectively, analogously as in the case of the Cl 2 (B) photodissociation.…”

Reaction dynamics within a cluster environment

“…Still considering the pick-up by helium nanodroplets, that of a rare gas atom has been modeled theoretically in a quantum description of the nanodroplet. [67][68][69] Subsequent formation of a rare gas dimer within the nanodroplet has been modelled also, both in full quantum and a hybrid quantum (helium)/classical (rare gas) approaches. 70,71 Helium density waves (possibly carrying vortices), which are produced by the pick-up of the Ne atoms, were shown to drive the Ne movements within the droplet and control their association as dimer.…”

Coexistence of vortex arrays and surface capillary waves in spinning prolate superfluid He4 nanodroplets

“…Superfluid 4 He droplets produced in the expansion of a cold helium gas [1] or by hydrodynamic instability of a liquid helium jet passing through the nozzle of a molecular beam apparatus [2] have been considered the ultimate inert matrix for molecular spectroscopy [3,4], constituting also an ideal test ground to study superfluidity at the nanoscale [5][6][7][8][9][10][11]. A series of experiments aiming at determining the appearance of large spinning 4 He droplets made of 10 8 -10 11 atoms [12][13][14][15][16][17][18] has motivated renewed interest in aspects such as how vortices are distributed inside helium droplets [19,20], how impurities are captured by the vortex lines they host, and how impurities arrange inside vortex-hosting droplets [21][22][23][24][25][26][27].…”