Publications (2022)
A new protonated molecule discovered in TMC-1: HCCNCH+& x22c6;
Authors: Agundez, M.; Cabezas, C.; Marcelino, N.; Fuentetaja, R.; Tercero, B.; de Vicente, P.; Cernicharo, J.
Journal: ASTRONOMY & ASTROPHYSICS
Publication date: 2022/03/24
DOI: 10.1051/0004-6361/202243396
Abstract: In recent years we have seen an important increase in the number of protonated molecules detected in cold dense clouds. Here we report the detection in TMC-1 of HCCNCH+, the protonated form of HCCNC, which is a metastable isomer of HC3N. This is the first protonated form of a metastable isomer detected in a cold dense cloud. The detection was based on observations carried out […]
An ab initio study of the photodissociation of the vinyl radical
Authors: Bouallagui, A.; Zanchet, A.; Banares, L.; Garcia-Vela, A.
Journal: PHYSICAL CHEMISTRY CHEMICAL PHYSICS
Publication date: 2022/03/23
DOI: 10.1039/d2cp00180b
Abstract: Photodissociation of the vinyl radical through pathways CH2CH -> CH2C + H, CH2CH -> CHCH + H, and CH2CH -> CH2 + CH is investigated by means of high-level ab initio calculations. Potential-energy curves (PECs) along the corresponding dissociating bond distance associated with the ground and several excited electronic states involved in the above fragmentation pathways, as well as the nonadiabatic couplings connecting the different states, are obtained. The findings of […]
Discovery of a new molecular ion, HC7NH+, in TMC-1 & x22c6;
Authors: Cabezas, C.; Agundez, M.; Marcelino, N.; Tercero, B.; Fuentetaja, R.; de Vicente, P.; Cernicharo, J.
Journal: ASTRONOMY & ASTROPHYSICS
Publication date: 2022/03/23
DOI: 10.1051/0004-6361/202142972
Abstract: We report the detection of the protonated form of HC7N in TMC-1. The discovery of the cation HC7NH+ was carried out via the observation of nine harmonically related lines in the Q-band using the Yebes 40 m radiotelescope. The observed frequencies allowed us to obtain the rotational constants B-0 = 553.938802 (160) MHz and D-0 = 3.6292 (705) Hz. The identification of HC7NH+ is further […]
Tunable Directional Emission and Collective Dissipation with Quantum Metasurfaces
Authors: Fernandez-Fernandez, D.; Gonzalez-Tudela, A.
Journal: PHYSICAL REVIEW LETTERS
Publication date: 2022/03/14
DOI: 10.1103/PhysRevLett.128.113601
Abstract: Subwavelength atomic arrays, recently labeled as quantum metamaterials, have emerged as an exciting platform for obtaining novel quantum optical phenomena. The strong interference effects in these systems generate subradiant excitations that propagate through the atomic array with very long lifetimes. Here, we demonstrate that one can harness these excitations to obtain tunable directional emission patterns and collective dissipative couplings when placing judiciously additional atoms nearby the atomic array. For doing that, we first characterize the optimal […]
Unraveling the Origin of Symmetry Breaking in H2O@C-60 Endofullerene Through Quantum Computations
Authors: Carrillo-Bohorquez, Orlando; Valdes, Alvaro; Prosmiti, Rita
Journal: CHEMPHYSCHEM
Publication date: 2022/03/14
Abstract: We explore the origin of the anomalous splitting of the 1(01) levels reported experimentally for the H2O@C-60 endofullerene, in order to give some insight about the physical interpretations of the symmetry breaking observed. We performed fully-coupled quantum computations within the multiconfiguration time-dependent Hartree approach employing a rigorous procedure to handle such computationally challenging problems. We introduce two competing physical models, and discuss the observed unconventional quantum patterns in terms of anisotropy in the interfullerene interactions, caused […]
Spin Many-Body Phases in Standard- and Topological-Waveguide QED Simulators
Authors: Bello, M.; Platero, G.; Gonzalez-Tudela, A.
Journal: PRX QUANTUM
Publication date: 2022/03/07
DOI: 10.1103/PRXQuantum.3.010336
Abstract: Waveguide QED has emerged as a powerful analog quantum simulator due to the possibility of mediating versatile spin-spin interactions with tunable sign, range, and even dimerization. Yet, despite their potential, the many-body phases emerging from these systems have only been scarcely explored. Here, we characterize the many-body phases of a large class of spin models that can be obtained in such waveguide-QED simulators and uncover, importantly, the existence of symmetry-protected topological phases with large-period magnetic […]
Organic Molecules in Interstellar Space: Latest Advances
Authors: Guelin, Michel; Cernicharo, Jose
Journal: FRONTIERS IN ASTRONOMY AND SPACE SCIENCES
Publication date: 2022/03/02
DOI: 10.3389/fspas.2022.787567
Abstract: Although first considered as too diluted for the formation of molecules in-situ and too harsh an environment for their survival, the interstellar medium has turned out to host a rich palette of molecular species: to date, 256 species, not counting isotopologues, have been identified. The last decade, and more particularly the last 2 years, have seen an explosion of new detections, including those of a number of complex organic species, which may be […]
Capturing quantum effects with quasi-classical trajectories in the D + H-3(+) -> H2D+ + H reaction
Authors: Braunstein, Matthew; Bonnet, Laurent; Roncero, Octavio
Journal: PHYSICAL CHEMISTRY CHEMICAL PHYSICS
Publication date: 2022/03/02
DOI: 10.1039/d1cp04244k
Abstract: We present quasi-classical trajectory (QCT) cross sections, rate constants, and product state distributions for the D + H-3(+) -> H2D+ + H reaction. Using the same H-4(+) potential surface, the rate constants obtained from several QCT-based methods correcting for zero-point effects by Gaussian binning the product H2D+ are compared to ring polymer molecular dynamics (RPMD) rate constants [Bulut et al., J. Phys. Chem. A, 2019, 123, 8766] which include quantum effects and to […]
A Benchmark Protocol for DFT Approaches and Data-Driven Models for Halide-Water Clusters
Authors: Rodriguez-Segundo, Raul; Arismendi-Arrieta, Daniel J.; Prosmiti, Rita
Journal: MOLECULES
Publication date: 2022/03/01
DOI: 10.3390/molecules27051654
Abstract: Dissolved ions in aqueous media are ubiquitous in many physicochemical processes, with a direct impact on research fields, such as chemistry, climate, biology, and industry. Ions play a crucial role in the structure of the surrounding network of water molecules as they can either weaken or strengthen it. Gaining a thorough understanding of the underlying forces from small clusters to bulk solutions is still challenging, which motivates further investigations. Through a systematic analysis of the […]
Detection of the S(1) Rotational Line of H-2 toward IRC+10216: A Simultaneous Measurement of the Mass-loss Rate and CO Abundance
Authors: Fonfria, J. P.; DeWitt, C. N.; Montiel, E. J.; Cernicharo, J.; Richter, M. J.
Journal: ASTROPHYSICAL JOURNAL LETTERS
Publication date: 2022/03/01
Abstract: We report the first detection of the S(1) pure rotational line of ortho-H-2 at 17.04 mu m in an asymptotic giant branch star, using observations of IRC+10216 with the Echelon-cross-echelle Spectrograph (EXES) mounted on the Stratospheric Observatory for Infrared Astronomy. This line, which was observed in a very high-sensitivity spectrum (rms noise similar or equal to 0.04% of the continuum), was detected in the wing of […]
Absolute total electron detachment and relative ionisation cross sections for O-2 (-) collisions with O-2 in the energy range (10-1500 eV)
Authors: Guerra, Carlos; Lozano, Ana, I; Mendes, Monica F.; Kumar, Sarvesh; Oller, Juan C.; Limao-Vieira, Paulo; Garcia, Gustavo
Journal: PLASMA SOURCES SCIENCE & TECHNOLOGY
Publication date: 2022/03/01
Abstract: Absolute total electron detachment cross for O-2 (-) collisions with O-2 are reported for impact energies ranging from 10 to 1600 eV as measured with a transmission-beam experimental apparatus. The primary anionic beam projectile is produced in a hollow cathode discharge-induced plasma, and the collisions with the neutral molecular target occur in a gas cell at a well-known constant pressure. The […]
Phase Diagram of 1+1D Abelian-Higgs Model and Its Critical Point
Authors: Chanda, Titas; Lewenstein, Maciej; Zakrzewski, Jakub; Tagliacozzo, Luca
Journal: PHYSICAL REVIEW LETTERS
Publication date: 2022/02/28
DOI: 10.1103/PhysRevLett.128.090601
Abstract: We determine the phase diagram of the Abelian-Higgs model in one spatial dimension and time (1 + 1D) on a lattice. We identify a line of first order phase transitions separating the Higgs region from the confined one. This line terminates in a quantum critical point above which the two regions are connected by a smooth crossover. We analyze the critical point and find compelling evidence for its description as the product […]
Methanol Negative Ion Fragmentation Probed in Electron Transfer Experiments
Authors: Isabel Lozano, Ana; Kumar, Sarvesh; Kerkeni, Boutheina; Garcia, Gustavo; Limao-Vieira, Paulo
Journal: JOURNAL OF PHYSICAL CHEMISTRY A
Publication date: 2022/02/24
Abstract: In this contribution, we report a novel comprehensive investigation on negative ion formation from electron transfer processes mediated by neutral potassium atom collisions with neutral methanol molecules employing experimental and theoretical methodologies. Methanol collision-induced fragmentation yielding anion formation has been obtained by time-of-flight mass spectrometry in the wide energy range of 19 to 275 eV in the lab frame. The negative ions formed in such a collision […]
[C II] 158 mu m line emission from Orion A II. Photodissociation region physics
Authors: Pabst, C. H. M.; Goicoechea, J. R.; Hacar, A.; Teyssier, D.; Berne, O.; Wolfire, M. G.; Higgins, R. D.; Chambers, E. T.; Kabanovic, S.; Guesten, R.; Stutzki, J.; Kramer, C.; Tielens, A. G. G. M.
Journal: ASTRONOMY & ASTROPHYSICS
Publication date: 2022/02/04
DOI: 10.1051/0004-6361/202140805
Abstract: Context. The [C II] 158 mu m fine-structure line is the dominant cooling line of moderate-density photodissociation regions (PDRs) illuminated by moderately bright far-ultraviolet (FUV) radiation fields. This makes this line a prime diagnostic for extended regions illuminated by massive stars. Aims. We aim to […]
Non-Gaussian entanglement swapping between three-mode spontaneous parametric down-conversion and three qubits
Authors: Casado, A. Agusti; Sabin, C.
Journal: PHYSICAL REVIEW A
Publication date: 2022/02/03
DOI: 10.1103/PhysRevA.105.022401
Abstract: In this work we study the production and swapping of non-Gaussian multipartite entanglement in a setup containing a parametric amplifier which generates three photons in different modes coupled to three qubits. We prove that the entanglement generated in this setup is of non-Gaussian nature. We introduce witnesses of genuine tripartite non-Gaussian entanglement, valid for both mode and qubit entanglement. Moreover, those witnesses show that the entanglement generated among the photons can be swapped to the […]