Article
Chemistry, Physical
Himani Tomer, Biplab Goswami, Paresh Modak, Mohammad Jane Alam, Shabbir Ahmad, Bobby Antony
Summary: This article explores the low-energy electron scattering from pyrrole and its isomers, such as 2-H pyrrole, cyclopropanecarbonitrile, and Z-2 butenenitrile, using R-matrix theory. The properties of the target molecules, including ionization energy, polarizability, dipole moment, rotational constant, principal moment of inertia, ground-state energy, and orbital energies, were investigated and compared. Resonances were observed in the elastic and inelastic channels, with a particularly significant resonance observed for Z-2 butenenitrile. Cross sections for elastic, excitation, and momentum-transfer processes were estimated, and the dissociative electron attachment channel for the pyrrolide anion was studied. The data presented in this article are important for modeling various fields such as astrophysics, astrochemistry, atmospheric science, and low-energy plasma, as well as for applications in biomedicine, radiation therapy, and pharmaceuticals.
JOURNAL OF PHYSICAL CHEMISTRY A
(2023)
Article
Chemistry, Multidisciplinary
Chengcheng Tang, Peter R. Taylor
Summary: We investigated the structure and spectra of Yariv reagents using DFT and ADC(2) methods. Dimer and model trimer formation was studied to understand their aggregation in aqueous solution. Our calculations confirmed that the strong bands in the visible spectrum result from enol-keto tautomerism within a single molecule, not aggregation.
Article
Chemistry, Multidisciplinary
Xuewen Fu, Zepeng Sun, Shaozheng Ji, Fang Liu, Min Feng, Byung-Kuk Yoo, Yimei Zhu
Summary: In this study, surface plasmons on a silver film were excited using a femtosecond laser, and the subsequent transient dynamics were investigated using photon-induced near-field electron microscopy (PINEM). The results showed that unlike silver nanowires and nanorods, the PINEM intensity on the silver film did not show any polarization dependence, providing a simple method for identifying the time zero in 4D ultrafast electron microscopy (UEM).
Article
Chemistry, Multidisciplinary
Difeng Yin, Yucen Li, Lingling Xia, Wenbo Li, Wei Chu, Jianping Yu, Miao Wu, Ya Cheng, Ming Hu
Summary: This study demonstrates an automated solid-liquid synthesis system using 3D microfluidic technology for gadopentetate dimeglumine with high efficiency. In-line analysis was conducted using UV-vis spectrometer to achieve automation of the system.
CHINESE CHEMICAL LETTERS
(2022)
Article
Chemistry, Physical
Christian T. Matthaei, Deb Pratim Mukhopadhyay, Anja Roeder, Lionel Poisson, Ingo Fischer
Summary: This study investigates the photodissociation dynamics of the trichloromethyl radical, CCl3, after excitation in the ultraviolet. The findings suggest that the dissociation to CCl + Cl-2 contributes to the photochemistry of CCl3.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2022)
Article
Chemistry, Physical
Lu Wu, George Schoendorff, Yuchen Zhang, Mourad Roudjane, Mark S. Gordon, Dong-Sheng Yang
Summary: Vibronic spectra of lutetium oxide seeded in supersonic molecule beams were investigated using mass-analyzed threshold ionization spectroscopy and second-order multiconfigurational quasi-degenerate perturbation theory. The abnormal vibrational intervals for both neutral and cation excited states were observed and attributed to vibrational perturbations induced by interactions with neighboring states.
JOURNAL OF CHEMICAL PHYSICS
(2022)
Article
Optics
Long Xu, Ilia Tutunnikov, Yehiam Prior, Ilya Sh Averbukh
Summary: This study investigates the excitation of asymmetric-top molecules by two-color femtosecond laser pulses, demonstrating three-dimensional orientation and enantioselective orientation for non-chiral and chiral molecules, respectively. The classical and quantum simulations show good agreement on short time scales, with quantum beats observed on longer time scales. The potential for using enantioselective orientation for enantiomer separation is discussed.
JOURNAL OF PHYSICS B-ATOMIC MOLECULAR AND OPTICAL PHYSICS
(2021)
Article
Biochemistry & Molecular Biology
Danhong Wang, Xueli Wang, Yanrong Jiang, Simin Cao, Peipei Jin, Haifeng Pan, Haitao Sun, Zhenrong Sun, Jinquan Chen
Summary: Methylated DNA/RNA nucleobases are important epigenetic marks and play a crucial role in targeted therapies. This study investigates the influence of methylation on the excited state dynamics of guanosine using femtosecond time-resolved spectroscopy. The results show that the effect of methyl substitution on the photophysical properties of guanosine is position sensitive, and the findings lay the foundation for further research on DNA/RNA strands containing these bases.
PHOTOCHEMISTRY AND PHOTOBIOLOGY
(2022)
Article
Chemistry, Multidisciplinary
Jiemin Qiu, Weihao Ye, Congcong Chen, Zhiqiang Xu, Chaofan Hu, Jianle Zhuang, Hanwu Dong, Bingfu Lei, Guangqi Hu, Yingliang Liu
Summary: In this study, three-component water-soluble carbon dots (OP-CDs) were successfully synthesized, which exhibited excellent UV absorption and high stability. The incorporation of OP-CDs and PVA resulted in a high-performance UV-shielding film with enhanced broad-spectrum UV shielding performance and improved mechanical properties, resistance to photocatalytic activity, and anti-UV aging ability.
JOURNAL OF INDUSTRIAL AND ENGINEERING CHEMISTRY
(2023)
Article
Chemistry, Multidisciplinary
Xing Jia, Longhuang Tang, Shenggang Liu, Heli Ma, Tianjiong Tao, Long Chen, Jian Wu, Chengjun Li, Xiang Wang, Linwen Zhang, Jidong Weng
Summary: A method for generating frequency-tunable microwave pulses using femtosecond laser excitation was proposed and demonstrated. The conversion of optical wave to microwave frequencies, ranging from 2.0 GHz to 19.7 GHz, was achieved by simple spatial-optical group delay adjustment. The system showed stability in terms of frequency and electrical amplitude, and was able to synthesize special microwave waveform pulses.
APPLIED SCIENCES-BASEL
(2021)
Article
Materials Science, Multidisciplinary
Sergey Kudryashov, Pavel Danilov, Nikita Smirnov, Alexey Levchenko, Michael Kovalev, Yulia Gulina, Oleg Kovalchuk, Andrey Ionin
Summary: Natural diamond under ultrafast visible-range excitation results in UV-VIS A-band photoluminescence with intense multi-peak optical-phonon progression. The A-band photoexcitation can occur through various transitions and processes, showing strong damping of progression intensities with different activation energies.
OPTICAL MATERIALS EXPRESS
(2021)
Article
Chemistry, Physical
Andrei G. Yakovlev, Alexandra S. Taisova, Zoya G. Fetisova
Summary: Chlorosomal carotenoids and bacteriochlorophyll in photosynthetic green bacteria efficiently participate in light harvesting. The excited-state dynamics in Cars from Chloroflexus aurantiacus chlorosomes show an ultrafast and large red shift, suggesting the presence of vibrational wavepacket or two potential minima in the S-2 state.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2021)
Article
Optics
Wei Meng, Pengbo Cai, Xiaoyan Fu, Hongwu Zhang
Summary: In this paper, a near-infrared luminescent material LiGaSiO4:Cr3+ with triple temperature detection function was successfully synthesized. The results showed that the material exhibited excellent near-infrared luminescence performance and achieved high temperature sensing sensitivity and accuracy through three fluorescence intensity ratio models. The study indicated that LiGaSiO4:Cr3+ has great potential in the application of temperature sensing.
JOURNAL OF LUMINESCENCE
(2022)
Article
Chemistry, Multidisciplinary
Sofia Goia, Matthew A. P. Turner, Jack M. Woolley, Michael D. Horbury, Alexandra J. Borrill, Joshua J. Tully, Samuel J. Cobb, Michael Staniforth, Nicholas D. M. Hine, Adam Burriss, Julie Macpherson, Ben R. Robinson, Vasilios G. Stavros
Summary: The study introduces a TA-SEC approach using BDD mesh electrodes to investigate early-stage photoinduced dynamics of reactive species. By electrochemically generating intermediates, the relaxation mechanisms of AQS and AH(2)QS are unravelled in the first 2.5 ns following UV absorption.
Article
Chemistry, Physical
Duy Duc Nguyen, Nykola C. Jones, Soren V. Hoffmann, Jens Spanget-Larsen
Summary: The UV absorbance spectra of trans-stilbene (DPE) and (E,E')-1,4-diphenyl-1,3-butadiene (DPB) were studied using Synchrotron Radiation Linear Dichroism (SRLD) spectroscopy with stretched polyethylene as an anisotropic solvent. The polarization data provided information about the transition moment directions of the observed spectral features. A comparison was made between the observed spectral bands and the results of quantum chemical calculations using LCOAO and TD-DFT with the CAM-B3LYP functional.
JOURNAL OF MOLECULAR STRUCTURE
(2023)
Article
Optics
Esrom Kifle, Pavel Loiko, Carolina Romero, Javier Rodriguez Vazquez de Aldana, Viktor Zakharov, Yulia Gurova, Andrey Veniaminov, Valentin Petrov, Uwe Griebner, Romain Thouroude, Mathieu Laroche, Patrice Camy, Magdalena Aguilo, Francesc Diaz, Xavier Mateos
Summary: This study presents an in-band pumped Tm3+, Ho3+ codoped waveguide laser, achieving colasing of Tm3+ and Ho3+ through bidirectional energy transfer. The maximum total output power and slope efficiency reached record highs for this type of laser, with the Ho laser reaching a maximum output power of 144 mW.
Article
Engineering, Electrical & Electronic
Moritz Wiehe, Marcos Fernandez Garcia, Michael Moll, Raul Montero, F. R. Palomo, Ivan Vila, Hector Munoz-Marco, Viorel Otgon, Pere Perez-Millan
Summary: The transient current technique is commonly used in silicon particle detector development, with recent advancements including the use of two-photon absorption for testing. This new method allows for higher resolution and preliminary measurements have shown promising results. Development of a compact setup is currently underway following successful initial experiments.
IEEE TRANSACTIONS ON NUCLEAR SCIENCE
(2021)
Article
Chemistry, Physical
Iker Leon, Raul Montero, Asier Longarte, Jose A. Fernandez
Summary: Laser spectroscopy in jets is a major method for obtaining structural data from molecular aggregates. Despite nearly 70 years of research, the assignment of mass-resolved IR spectrum of water dimer remains controversial.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2021)
Article
Materials Science, Multidisciplinary
Shuo Sun, Xiaoli Sun, Feng Ren, Carolina Romero, Javier R. Vazquez de Aldana, Yuechen Jia, Feng Chen
Summary: In this study, tapered circular depressed-cladding waveguides were fabricated in Nd:YAG crystal by femtosecond laser direct writing, allowing for the realization of efficient Q-switched mode-locked lasers with silver nanoparticles as saturable absorbers. The tapered waveguides were found to suppress multi-mode guiding and ensure fundamental-mode output, paving the way for the development of three-dimensional waveguides for on-chip ultrafast laser sources.
RESULTS IN PHYSICS
(2021)
Article
Instruments & Instrumentation
S. Pape, M. Fernandez Garcia, M. Moll, R. Montero, F. R. Palomo, I Vila, M. Wiehe
Summary: A tabletop TPA-TCT set-up built at CERN was used to investigate non-irradiated and irradiated PIN diodes, as well as non-irradiated 5 x 5-multipad HPK LGAD. The method demonstrated its intrinsic three-dimensional spatial resolution and ability to determine the boundaries of the device under test's active volume. A method to eliminate single photon absorption background was discussed.
JOURNAL OF INSTRUMENTATION
(2022)
Article
Optics
Azahara Almagro-Ruiz, Sebastian Pape, Hector Munoz-Marco, Moritz Wiehe, Esteban Curras, Marcos Fernandez-Garcia, Michael Moll, Raul Montero, Francisco Rogelio Palomo, Cristian Quintana, Ivan Vila, Pere Perez-Millan
Summary: A fiber laser system emitting configurable ultrashort femtosecond pulses has been developed for the two-photon absorption transient current technique. The system provides the required optical specifications for localized characterization of semiconductor radiation detectors and has been validated through measurements in a silicon detector.
Article
Optics
Matthias J. Grotevent, Sergii Yakunin, Dominik Bachmann, Carolina Romero, Javier R. Vazquez de Aldana, Matteo Madi, Michel Calame, Maksym Kovalenko, Ivan Shorubalko
Summary: This paper demonstrates a Fourier-transform waveguide spectrometer using HgTe-quantum-dot-based photoconductors, with a spectral response up to 2 μm and a spectral resolution of 50 cm(-1). The small size of the spectrometer enables its integration into consumer electronics and space devices.
Article
Instruments & Instrumentation
S. Pape, E. Curras, M. Fernandez Garcia, M. Moll, R. Montero, F. R. Palomo, I Vila, M. Wiehe, C. Quintana
Summary: The Low Gain Avalanche Detector (LGAD) technology has great potential for silicon timing detectors and is currently the subject of intensive research. Recent studies have shown that the gain of LGADs is strongly influenced by the charge carrier density in the gain layer. The Two Photon Absorption-Transient Current Technique (TPA-TCT) was used to study the gain reduction related to charge carrier density by providing information on drift velocity and electric field. A compact TPA-TCT setup was developed at CERN to measure current transients for a 285 μm thick PIN and LGAD device, and methods to extract electric field information were employed to verify the gain reduction related to charge carrier density. This study also achieved spatial resolution of the gain layer in LGAD for the first time.
NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT
(2022)
Article
Chemistry, Physical
Alvaro Peralta Conde, Iker Lamas, Marina Sanchez Albaneda, Cruz Mendez, Asier Longarte, Raul Montero
Summary: This study presents a simple method for generating sub-20 fs UV pulses (264 nm) using third-harmonic generation in an air-plasma filament formed by focusing the fundamental 800 nm beam directly in the lab open-atmosphere. These pulses are used to track the relaxation through the conical intersection that couples the S2 and S1 states in the benchmark molecule of naphthalene. The obtained transients, with a resolution of about 25 fs, exhibit distinguishable quantum beat patterns. The assignment of these oscillations to specific modes in the lower S1 state and electronic coherence between the coupled states is discussed.
CHEMICAL PHYSICS LETTERS
(2023)
Article
Chemistry, Multidisciplinary
E. Alonso, A. Peralta Conde
Summary: Although there is a lack of theoretical description for some critical aspects of MALDI results, a new phenomenological approach based on a simplified three-layer laser-matter interaction process has been presented in this work. The simulations show good agreement with the experimental results, allowing for distinction between desorption and ablation regimes and estimation of the critical fluence for the transition between the two regimes.
Article
Materials Science, Biomaterials
Ruth Prieto-Montero, Aitor Diaz Andres, Alejandro Prieto-Castaneda, Andrea Tabero, Asier Longarte, Antonia R. Agarrabeitia, Angeles Villanueva, Maria J. Ortiz, Raul Montero, David Casanova, Virginia Martinez-Martinez
Summary: The study presents a simple and easily accessible molecular design of heavy atom free photosensitizers for photodynamic therapy. The effect of alkyl groups on the photophysical properties is analyzed experimentally and computationally, providing mechanistic insights. The potential applicability of the most promising compound as a theragnostic agent is demonstrated in in vitro assays.
JOURNAL OF MATERIALS CHEMISTRY B
(2022)
Article
Chemistry, Physical
Iker Lamas, Jorge Gonzalez, Asier Longarte, Raul Montero
Summary: We performed time-resolved experiments on aniline, an aromatic chromophore, in water after excitation at 267 nm. A transient state with the electron located on the solvent molecule was observed in addition to the bright pp* excitation. We propose that this transient state corresponds to the ps* state along the N-H bond, which eventually leads to the formation of a fully solvated electron and cation. This ionization process occurs simultaneously with the pp* photophysical channel, resulting in the characteristic 1 ns fluorescence lifetime.
JOURNAL OF CHEMICAL PHYSICS
(2023)