Intense-Field Double Detachment of Electrostatically Bound F^–(NF₃)_n Cluster Anions

Abstract

The interaction of intense laser pulses with size-selected F(-)(NF3)n clusters is experimentally studied. Intense-field double- and multiple-detachment processes in the isolated atomic F(-) anion and in electrostatically bound F(-)(NF3) dimer and F(-)(NF3)2 trimer systems are directly compared. Both dimer and trimer systems are found to exhibit similar enhancement of the highly nonlinear processes, with respect to the atomic system, as reflected in significantly lower saturation intensities. The dependencies of different product channels as a function of laser peak intensity, polarization ellipticity, and laser pulse shape are presented, indicating an efficient nonrescattering mechanism.

Intense-Field Multiple-Detachment of F2¯: Competition with Photodissociation

“…19 Nevertheless, studies as a function of polarization ellipticity for the atomic F¯ as well as for several molecular and cluster anions were found to be not consistent with semiclassical rescattering dynamics. 5,[19][20][21] Furthermore, Kandhasamy et al proposed dissociation on highly excited (SF6 + )* states with a dication core and a Rydberg electron to account for the observed SF5 + + F events with high kinetic energy release (KER), produced by intense-field interaction with the molecular SF6¯ anion. 20 In the absence of a successful theoretical picture for intense-field interactions with anionic systems, it is important to experimentally examine the nature of intense-field multiple detachment of molecular anions.…”

Simultaneous 3D coincidence imaging of cationic, anionic, and neutral photo-fragments

“…In our experimental setup, [28][29][30][31][32] anions are produced in a cold ion source, equipped with a pulsed electron gun and an Even-Lavie pulsed valve. 34 by dissociative electron attachment to the NF precursor sample, 35,36 supersonically expanded with Ar carrier gas.…”

“…[25][26][27] Using a fast anion beam target and a similar concept of an electrostatic spectrometer, we are able to investigate different competing dissociation and electron detachment channels in intense field interaction with atomic, molecular, and cluster anions. [28][29][30][31][32][33] The photofragment spectrometer design allows coincidence detection of all the possible dissociation products on the same detector, including the anionic, cationic, and neutral fragments. In the present study, we describe the design, calibration, and optimization of the photofragment spectrometer as well as an analytic model for extracting channel specific KER spectra from 3D coincidence imaging data.…”

Изменение Нормальных Координат И Геометрических Параметров Молекулы В Лазерном Поле

“…При на-личии вырождения, например в линейной молекуле, условие (16) нарушается. Это приводит к невозмож-ности факторизации в (14). Если для определенности положить колебательные моды k = 1, 2 вырожденными В качестве примера здесь можно привести простей-шую линейную симметричную трехатомную молеку-лу CO 2 с четырьмя колебательными степенями свободы.…”

“…Среди достижений последних лет можно указать исследование лазерного химического синтеза [1,2], лазерный контроль движения молекуляр-ных электронов [3,4] и изменения оптических свойств газа когерентно вращающихся молекул [5][6][7][8], спектро-скопию комбинационного [9] и когерентного антисток-сова рассеяния света [10], перегруппировку атомов при лазерной фрагментации молекул [11], наблюдение двухэлектронного отрыва от анионов SF − 6 [12,13] и F − (NF 3 ) n [14]. В недавнем эксперименте [15] была продемонстри-рована важная роль " одетого полем" атома при рас-сеянии на нем электрона в поле лазерного излучения (laser-assisted electron scattering, LAES), теоретически рассмотренного в работе [16].…”