2A), which corresponds to the energy of an electron from SB12. The PI cross section of the 1t 1 orbital has a prominent maximum in the 1t 1 → kt 2 (where k indicates a continuum state) channel around 2.5 eV (see the blue curve in Fig. We did not observe any CF 2 + in our ion mass spectra. Because of the prominence of the latter two states in the photoelectron spectrum, we focus exclusively on the A ~ and X ~ states, the potential energy surfaces of which are shown in Fig. The C ~ state dissociates into CF 2 + + F 2 and CF 2 + + F + F, while the B ~, A ~, and X ~ states dissociate into CF 3 + + F ( 38, 39). PI from one of these orbitals results in CF 4 + in the states C ~ 2 T 2, B ~ 2E, A ~ 2 T 2, or X ~ 2 T 1. The ionization potentials of the four outer-valence orbitals of CF 4 (. Next, we investigate the time delay in the recoil frame of CF 4, where we find a pronounced asymmetry in the delays for low kinetic energies. In a first step, we investigate the shape resonance found in the vicinity of the electronic ground state of CF 4 +, where we find a PI time delay of up to ∼600 as, relative to argon, which is caused by the resonance.
#Cf4 molecular geometry full
In contrast to prior work, we achieved full angular- and final-state resolution. Accessing PI dynamics in the molecular frame can give detailed insight into the ionization process of molecules and has drawn recent theoretical interest ( 16, 29– 31). Previous work on CO ( 28) has been limited to a left-right asymmetry, previously called “stereo” time delay ( 29). This combination of techniques makes it possible to access ionization time delays in the molecular frame of a molecule. Our experimental approach is based on attosecond interferometry, also known as RABBIT (reconstruction of attosecond beating by interference of two-photon transitions) ( 19– 21), in combination with an electron-ion coincident three-dimensional (3D) momentum imaging detection scheme (COLTRIMS) ( 22, 23), as recently applied to atoms and linear molecules ( 24– 28). Our technique thereby simultaneously reveals the temporal and the angular manifestations of shape resonances in CF 4 and provides unprecedented information on their PI dynamics. In this work, we demonstrate an experimental method that completely resolves the attosecond PI dynamics of nonlinear molecules in their recoil frame and the final states of the cation. Our experimental and theoretical results establish a broadly applicable approach to space- and time-resolved photoionization dynamics in the molecular frame. Comparison with quantum-scattering calculations traces the asymmetries to the interference of a small subset of partial waves at low kinetic energies and, additionally, to the interference of two overlapping shape resonances in the HOMO-1 channel. We find delays of up to ∼600 as in the ionization out of the highest occupied molecular orbital (HOMO) with a strong dependence on the emission direction and a pronounced asymmetry along the dissociation axis. This technique provides insights into the spatiotemporal photoionization dynamics of molecular shape resonances. Here, we present measurements of recoil frame angle-resolved photoionization delays in the vicinity of shape resonances of CF 4. Shape resonances play a central role in many areas of science, but the real-time measurement of the associated many-body dynamics remains challenging.
Therefore, the molecular geometry of CF 4 is Tetrahedral. From the A-X-N table below, we can determine the molecular geometry. We can ignore ‘N’ since there are no lone pairs.
Therefore, that would give us AX 4 for the CF 4 molecule. ‘N’ represents the number of lone pairs attached to the central atom. In this case, there are four Fluorine atoms bonded to the central Carbon atom. ‘X’ represents the number of atoms bonded to the central atom. This can also be determined by using the steric number or the A-X-N method. This results in a Tetrahedral molecular geometry, as shown.
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