Related papers: Ab initio spectroscopic characterization of the ra…
The methoxy radical, CH$_3$O, has long been studied experimentally and theoretically by spectroscopists because it displays a weak Jahn-Teller effect in its electronic ground state, combined with a strong spin-orbit interaction. In this…
We present the first variational calculation of a hot temperature ab initio line list for the CH$_3$ radical. It is based on a high level ab initio potential energy surface and dipole moment surface of CH$_3$ in the ground electronic state.…
This work presents a comprehensive theoretical investigation of key isomers of C2H4N2 using state-of-the-art quantum chemical methods. The objective is to characterize their molecular structures, spectroscopic constants, and electronic…
Full-dimensional (12D) vibrational states of the methanol molecule (CH$_3$OH) have been computed using the GENIUSH-Smolyak approach and the potential energy surface from Qu and Bowman (2013). All vibrational energies are converged better…
We report the observation and analysis of spectra in part of the near-infrared spectrum of C$_2$H, originating in rotational levels in the ground and lowest two excited bending vibrational levels of the ground $\tilde{X}\,^2\Sigma^+$ state.…
The studies of the complex molecular emission lines in millimeter and submillimeter wavelengths towards the hot molecular cores demonstrate valuable details about the chemical complexity in the interstellar medium (ISM). We presented the…
The torsional Raman spectra of two astrophysically detected isotopologues of dimethyl-ether, ($^{12}$CH$_3$O$^{12}$CH$_3$ and $^{13}$CH$_3$O$^{12}$CH$_3$), have been recorded at room temperature and cooled in supersonic jet, and interpreted…
We have demonstrated that a supersonic beam of methyl radicals (CH$_3$) in the ground rotational state of both $para$ and $ortho$ species has been slowed down to standstill with a magnetic molecular decelerator, and successfully captured…
We present a new global study of the millimeter (mm) wave, submillimeter (sub-mm) wave, and terahertz (THz) spectra of the lowest three torsional states of methyl mercaptan (CH$_3$SH). New measurements have been carried out between 50 and…
Electric dipole and polarizability surfaces are developed for the methanol (CH$_3$OH) molecule using ab initio electronic structure data, computed at the CCSD/aug-cc-pVTZ level of theory, and equivariant neural networks. These property…
Small polycyclic aromatic hydrocarbons and somewhat larger cyano derivatives were detected in the cold dark cloud TMC-1 recently. Their formation from smaller hydrocarbons is not well understood, in part because abundances of many species…
The inelastic cross sections and rate coefficients for the rotational excitation of methanimine (CH$_2$NH) by cold H$_2$ have been determined quantum mechanically based on a new highly correlated five-dimensional potential energy surface.…
The infrared spectra of the weakly-bound dimers OCS-HCCCCH, in the region of the nu1 fundamental band of OCS (2050 cm-1), and N2O-HCCCCH, in the region of the nu1 fundamental band of N2O (2200 cm-1), were observed in a pulsed supersonic…
We develop the multi-scale ab-initio scheme for correlated electrons (MACE) for transitionmetal-oxide heterostructures, and determine the parameters of the low-energy effective model. By separating Ti t2g bands near the Fermi level from the…
We have started a measurement campaign of numerous methanol isotopologs in low-lying torsional states in order to provide extensive line lists for radio astronomical observations from an adequate spectroscopic model and to investigate how…
High level ab initio calculations were undertaken on the CH$_2$OO anion and neutral species to predict the electron affinity and anion photoelectron spectrum. The electron affinity of CH$_2$OO, 0.567 eV, and barrier height for dissociation…
We report the detection of the propargyl radical (CH2CCH) in the cold dark cloud TMC-1 in the lambda 3 mm wavelength band. We recently discovered this species in space toward the same source at a wavelength of lambda 8 mm. In those…
Observations with the Short Wavelength Spectrometer (SWS) onboard the {\it Infrared Space Observatory} (ISO) have led to the first detection of the methyl radical ${\rm CH_3}$ in the interstellar medium. The $\nu_2$ $Q-$branch at 16.5…
The region 1273-1290 cm$^{-1}$ of the $\nu$4 fundamental of the simplest Criegee intermediate, CH$_2$OO, has been measured using a quantum cascade laser transient absorption spectrometer, which offers greater sensitivity and spectral…
We recently reported the first identification of rotational transitions of methyl formate (HCOOCH$_{3}$) in the second torsionally excited state toward Orion Kleinmann-Low (KL) observed with the Nobeyama 45 m telescope. In combination with…