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Related papers: Computing Anharmonic Infrared Spectra of Polycycli…

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We recently introduced the Alchemical Integral Transform (AIT) enabling the prediction of energy differences, and guessed an Ansatz to parametrize space $\pmb{r}$ in some alchemical change $\lambda$. Here, we present a rigorous derivation…

Chemical Physics · Physics 2024-12-10 Simon León Krug , O. Anatole von Lilienfeld

Following the tentative identification of the blue luminescence in the Red Rectangle by Vijh et al. (2005), we compute absolute fluxes for the vibrational IR emission and phosphorescence bands of three small polycyclic aromatic…

Astrophysics · Physics 2009-11-11 G. Mulas , G. Malloci , C. Joblin , D. Toublanc

Ubiquitous unidentified infrared emission bands are seen in many astronomical sources. Although these bands are widely, if not unanimously, attributed to the collective emission from polycyclic aromatic hydrocarbons, no single species from…

Utilizing the data and tools provided through the NASA Ames PAH IR Spectroscopic Database (PAHdb), we study the PAH component of over 900 Spitzer-IRS galaxy spectra. Employing a database-fitting approach, the average PAH size, the PAH size…

Astrophysics of Galaxies · Physics 2022-06-01 A. Maragkoudakis , C. Boersma , P. Temi , J. D. Bregman , L. J. Allamandola

We present a systematic study of mid-infrared spectra of galaxies including star-forming galaxies and Active Galactic Nuclei observed with JWST MIRI-MRS and NIRSpec-IFU. We focus on the relative variations of the 3.3, 6.2, 7.7, 11.3, 12.7…

We present the experimental InfraRed Multiple Photon Dissociation (IRMPD) spectrum and fragmentation mass spectrum of the irregular, cationic PAH dibenzo[a,l]pyrene (C$_{24}$H$_{14}^+$) in the 6-40 $\mu$m / 250-1650 cm$^{-1}$ range. The use…

Accurate and efficient simulation of infrared (IR) and Raman spectra is essential for molecular identification and structural analysis. Traditional quantum chemistry methods based on the harmonic approximation neglect anharmonicity and…

Chemical Physics · Physics 2025-10-07 Shengjiao Ji , Yujin Zhang , Zihan Zou , Bin Jiang , Jun Jiang , Yi Luo , Wei Hu

Real-time monitoring of individual particles from atmospheric aerosols was performed by means of a specifically developed single-particle fluorescence spectrometer (SPFS). The observed fluorescence was assigned to particles bearing…

The abundance of polycyclic aromatic hydrocarbons (PAHs) in low- and high-metallicity galaxies has been widely discussed since the time when detailed infrared data for extragalactic objects were first obtained. On the scales of entire…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-15 M. S. Khramtsova , D. S. Wiebe , P. A. Boley , Ya. N. Pavlyuchenkov

We present a new methodology for simulating mid-infrared emission from polycyclic aromatic hydrocarbons (PAHs) in galaxy evolution simulations. To do this, we combine theoretical models of PAH emission features as they respond to varying…

This work explores how small molecules sound. Infrared (IR) spectra of HCl, H2O, NH3, and acetone are mapped into the audible range using a simple anharmonic oscillator model and NIST vibrational data. Comparing harmonic and anharmonic…

Chemical Physics · Physics 2026-01-07 Sophia H. Kim , Eric J. Heller

Polycyclic Aromatic Hydrocarbons are prevalent in the universe and interstellar medium but are primarily attributed to anthropogenic sources on Earth, such as fossil fuel combustion and firewood burning. Drawing upon the idea of PAHs as…

Earth and Planetary Astrophysics · Physics 2025-01-14 Dwaipayan Dubey , Ravi Kopparapu , Barbara Ercolano , Karan Molaverdikhani

Examination of thermal expansion of two-dimensional (2D) nanomaterials is a challenging theoretical task with either ab-initio or classical molecular dynamics simulations. In this regard, while ab-initio molecular dynamics (AIMD)…

Materials Science · Physics 2021-10-22 Bohayra Mortazavi , Ali Rajabpour , Xiaoying Zhuang , Timon Rabczuk , Alexander V. Shapeev

We present a quantitative model for the infrared emission from dust in the diffuse interstellar medium. The model consists of a mixture of amorphous silicate grains and carbonaceous grains, each with a wide size distribution ranging from…

Astrophysics · Physics 2008-11-26 Aigen Li , B. T. Draine

As images and spectra from ISO and Spitzer have provided increasingly higher-fidelity representations of the mid-infrared (MIR) and Polycyclic Aromatic Hydrocarbon (PAH) emission from galaxies and galactic and extra-galactic regions, more…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-20 Daniela Calzetti

We present results on the variation of 7.7 micron Polycyclic Aromatic Hydrocarbon (PAH) emission in galaxies spanning a wide range in metallicity at z ~ 2. For this analysis, we use rest-frame optical spectra of 476 galaxies at 1.37 < z <…

Classification and identification of amino acids in aqueous solutions is important in the study of biomacromolecules. Laser Induced Breakdown Spectroscopy (LIBS) uses high energy laser-pulses for ablation of chemical compounds whose…

Machine Learning · Computer Science 2021-05-26 Piyush K. Sharma , Gary Holness , Poopalasingam Sivakumar , Yuri Markushin , Noureddine Melikechi

Polycyclic Aromatic Hydrocarbon (PAH) molecules have been long adjudged to contribute to the frequently detected distinct emission features at 3.3, 6.2, 7.7, 8.6, 11.2 and 12.7 {\mu}m with weaker and blended features distributed in the 3-20…

Astrophysics of Galaxies · Physics 2020-03-25 Mridusmita Buragohain , Amit Pathak , Itsuki Sakon , Takashi Onaka

We present a comprehensive mid-infrared spectroscopic survey of 124 Herbig Ae/Be stars using newly processed Spitzer/IRS spectra from the newly released CASSISjuice database. Based on prominent dust and molecular signatures (polycyclic…

Solar and Stellar Astrophysics · Physics 2025-06-18 R. Arun , Blesson Mathew , B. Shridharan , K. Ujjwal , Akhil Krishna R , G. Maheswar , Sreeja S. Kartha

Pulmonary Arterial Wedge Pressure (PAWP) is an essential cardiovascular hemodynamics marker to detect heart failure. In clinical practice, Right Heart Catheterization is considered a gold standard for assessing cardiac hemodynamics while…

Computer Vision and Pattern Recognition · Computer Science 2024-04-09 Prasun C Tripathi , Sina Tabakhi , Mohammod N I Suvon , Lawrence Schöb , Samer Alabed , Andrew J Swift , Shuo Zhou , Haiping Lu
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