- ID:
- ivo://CDS.VizieR/J/MNRAS/434/1469
- Title:
- ExoMol line lists for SiO
- Short Name:
- J/MNRAS/434/1469
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Accurate rotation-vibration line lists are calculated for silicon monoxide. Line lists are presented for the main isotopologue, ^28^Si^16^O, and four monosubstituted isotopologues ^29^Si^16^O, ^30^Si^16^O, ^28^Si^17^O and ^28^Si^18^O, in their ground electronic states. These line lists are suitable for high temperatures (up to 9000K) including those relevant to exoplanetary atmospheres and cool stars. A combination of empirical and ab initio methods is used: the potential energy curves are determined to high accuracy by fitting to extensive data from analysis of both laboratory and sunspot spectra; a high quality ab initio dipole moment curve is calculated at the large basis set, multi-reference configuration interaction (MRCI) level. A partition function plus full line lists of rotation-vibration transitions are made available in an electronic form as supplementary data to this article and at www.exomol.com.
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- ID:
- ivo://CDS.VizieR/J/MNRAS/459/3890
- Title:
- ExoMol line lists for SO2
- Short Name:
- J/MNRAS/459/3890
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Sulphur dioxide is well-known in the atmospheres of planets and satellites, where its presence is often associated with volcanism, and in circumstellar envelopes of young and evolved stars as well as the interstellar medium. This work presents a line list of 1.3 billion 32S16O2 vibration-rotation transitions computed using an empirically-adjusted potential energy surface and an ab initio dipole moment surface. The list gives complete coverage up to 8000cm^-1^ (wavelengths longer than 1.25um) for temperatures below 2000K. Infrared absorption cross sections are recorded at 300 and 500C are used to validated the resulting ExoAmes line list. The line list is made available in electronic form as supplementary data to this article and at www.exomol.com.
- ID:
- ivo://CDS.VizieR/J/MNRAS/472/3648
- Title:
- ExoMol line lists. PO and PS spectra
- Short Name:
- J/MNRAS/472/3648
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Comprehensive line lists for phosphorus monoxide (PO) and phosphorus monosulphide (PS) in their X2Pi electronic ground state are presented. The line lists are based on new ab initio potential energy (PEC), spin-orbit (SOC) and dipole moment (DMC) curves computed using the MRCI+Q-r method with aug-cc-pwCV5Z and aug-cc-pV5Z basis sets. The nuclear motion equations (i.e. the rovibronic Schroedinger equations for each molecule) are solved using the program Duo. The PECs and SOCs are refined in least-squares fits to available experimental data. Partition functions, Q(T), are computed up to T=5000K, the range of validity of the line lists. These line lists are the most comprehensive available for either molecule. The characteristically sharp peak of the Q-branches from the spin-orbit split components give useful diagnostics for both PO and PS in spectra at infrared wavelengths. These line lists should prove useful for analysing observations and setting up models of environments such as brown dwarfs, low-mass stars, O-rich circumstellar regions and potentially for exoplanetary retrievals. Since PS is yet to be detected in space, the role of the two lowest excited electronic states (a4Pi and B2Pi) are also considered. An approximate line list for the PS X - B electronic transition, which predicts a number of sharp vibrational bands in the near ultraviolet, is also presented. The line lists are also available from the ExoMol (www.exomol.com) database.
- ID:
- ivo://CDS.VizieR/J/MNRAS/477/1520
- Title:
- ExoMol line lists. SiS
- Short Name:
- J/MNRAS/477/1520
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- SiS has long been observed in the circumstellar medium of the carbon-rich star IRC+10216 CW Leo. Comprehensive and accurate rotation-vibrational line lists and partition functions are computed for 12 isotopologues of silicon sulphide in its ground electronic state. The calculations employ an existing spectroscopically accurate potential energy curve (PEC) derived from experimental measurements and a newly-computed ab initio dipole moment curve (DMC).
- ID:
- ivo://CDS.VizieR/J/MNRAS/478/270
- Title:
- ExoMol line lists. Spectra of SH and NS
- Short Name:
- J/MNRAS/478/270
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Line lists for sulphur containing molecules SH (the mercapto radical) and NS are computed as part of the ExoMol project. These line lists consider transitions within the ground electronic state for isotopologues of SH and NS. Ab initio potential energy (PEC), and spin-orbit coupling (SOC) curves are computed and then improved by fitting to experimentally observed transitions. Fully ab initio dipole moment curves (DMCs) computed at the high level of theory are used to produce the final line list. For SH, our fit gives a root-mean-square (rms) error of 0.03cm^-1^ between the observed (v_max_=4, J_max_=34.5) and calculated transitions wavenumbers; this is extrapolated such that all possible X bound states are considered. For ^32^SH the resulting line list contains about 81,000 transitions and 2300 rovibronic states, considering levels up to vmax=14 and Jmax=60.5. For NS the refinement using a combination of experimentally-determined frequencies and derived energy levels rms errors of 0.002cm^-1^ and 0.03cm^-1^, respectively. Each NS calculated line lists includes around 3.2 million transitions and 31000 rovibronic states with a vibrational range up to v=53 and rotational range to J=235.5 which covers up to 39000cm^-1^. Both line lists should be complete for temperatures up to 5000K. Example spectra simulated using this line list are shown and comparisons made to the existing data in the CDMS database.
- ID:
- ivo://CDS.VizieR/J/MNRAS/473/5324
- Title:
- ExoMol line lists. XXIV. SiH
- Short Name:
- J/MNRAS/473/5324
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- SiH has long been observed in the spectrum of our Sun and other cool stars. Computed line lists SiGHTLY for the main isotopologues of silicon monohydride, ^28^SiH, ^29^SiH, ^30^SiH and ^28^SiD are presented. These line lists consider rotation-vibration transitions within the ground X ^2^{Pi} electronic state as well as transitions to the low-lying A ^2^{Delta} and a ^4^{Sigma}^-^ states. Ab initio potential energy (PECs) and dipole moment curves (DMCs) along with spin-orbit and electronic-angular-momentum couplings between them are calculated using the MRCI level of theory with the MOLPRO package. The PEC for the ground X state is refined to available experimental data with a typical accuracy of around 0.01cm^-1^ or better. The ^28^SiH line list includes 11,785 rovibronic states and 1,724,841 transitions with associated Einstein-A coefficients for angular momentum J up to 82.5 and covering wavenumbers up to 31340cm^-1^ (>0.319um). Spectra are simulated using the new line list and comparisons made with various experimental spectra. These line lists are applicable up to temperatures of ~5000K, making them relevant to astrophysical objects such as exoplanetary atmospheres and cool stars and opening up the possibility of detection in the interstellar medium.
- ID:
- ivo://CDS.VizieR/J/MNRAS/480/3397
- Title:
- ExoMol line lists XXXI: C_2_
- Short Name:
- J/MNRAS/480/3397
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Accurate line lists for the carbon dimer, C_2_, are presented. These line lists cover rovibronic transitions between the eight lowest electronic states: X, A, B, B', a, b, c, d. Potential energy curves (PECs) and transition dipole moment curves are computed on a large grid of geometries using the aug-cc-pwCVQZ-DK/MRCI level of theory including core and core-valence correlations and scalar relativistic energy corrections. The same level of theory is used to compute spin-orbit and electronic angular momentum couplings. The PECs and couplings are refined by fitting to the empirical (MARVEL) energies of C_2_ using the nuclear-motion program Duo. The transition dipole moment curves are represented as analytical functions to reduce the numerical noise when computing transition line strengths. Partition functions, full line lists, Lande-factors and lifetimes for three main isotopologues of C_2_ (^12^C_2_, ^13^C_2_ and ^12^C^13^C) are made available.
- ID:
- ivo://CDS.VizieR/J/MNRAS/486/2351
- Title:
- ExoMol line lists. XXXII. MgO
- Short Name:
- J/MNRAS/486/2351
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Line lists for magnesium oxide are computed and extensive comparisons are made with existing experimental spectra. The LiTY line lists cover all ro-vibration transitions within the five lowest-lying electronic states (X, a, A, B, b) and five isotopologues ^24^Mg^16^O, ^25^Mg^16^O, ^26^Mg^16^O, ^24^Mg^17^O, ^24^Mg^18^O. The calculation use potential energy cures, spin-orbit and electronic angular momentum couplings curves determined by fitting to empirical energy levels which are reproduced to within 0.01cm^-1^ in most cases. The computed wavefunctions combined with ab initio dipole moment curves giving transition intensities and excited state radiative lifetimes which are compared with laboratory measurements. The ^24^Mg^16^O line list comprises 186842 (J<=320) ro-vibronic states and 72833173 transitions with for angular momenta, J, up to 300 and covering energies in wavenumber up to 33000cm^-1^. The line list are suitable for temperatures up to about 5000K. They are relevant to astrophysical studies of exoplanet atmospheres, cool stars and brown drafts.
- ID:
- ivo://CDS.VizieR/J/MNRAS/470/882
- Title:
- ExoMol Line List XXI: Nitric Oxide (NO)
- Short Name:
- J/MNRAS/470/882
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Line lists for the ground electronic ground state for the parent isotopologue of nitric oxide and five other major isotopologues are presented. The line lists are constructed using empirical energy levels (and line positions) and high-level ab inito intensities. The energy levels were obtained using a combination of two approaches, from an effective Hamiltonian and from solving the rovibronic Schroedinger equation variationally. The effective hamiltonian model was obtained through a fit to the experimental line positions of NO available in the literature for all six isotopologues using the programs SPFIT and SPCAT. The variational model was built through a least squares fit of the ab inito potential and spin-orbit curves to the experimentally derived energies and experimental line positions of the main isotopologue only using the Duo program. The ab inito potential energy, spin-orbit and dipole moment curves (PEC, SOC and DMC) are computed using high-level ab inito methods and the MARVEL method is used to obtain energies of NO from experimental transition frequencies. The line lists are constructed for each isotopologue based on the use of the most accurate energy levels and the ab inito DMC. Each line list covers a wavenumber range from 0-40000cm^-1^ with approximately 22,000 rovibronic states and 2.3-2.6 million transitions extending to J=184.5 and v=51. The computed NO line lists are the most comprehensive to date, covering a wider wavenumber and temperature range compared to both the HITRAN and HITEMP databases. These line lists are also more accurate than those used in HITEMP. The full line lists are available from www.exomol.com.
- ID:
- ivo://CDS.VizieR/J/MNRAS/488/2332
- Title:
- ExoMol line list XXXIV. PH
- Short Name:
- J/MNRAS/488/2332
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A rovibronic line list for the ground (X^3^{Sigma}^-^) and first excited (a^1^{Delta}) states of phosphinidene, 31PH, is computed. The line list is designed for studies of exoplanetary and cool stellar atmospheres with temperatures up to 4000K. A combination of empirical and ad initio data are used to produce the line list: potential energy curves (PECs) are fitted using experimental transition frequencies; these transitions are reproduced with a root mean square error of 0.01cm^-1^. The nuclear Schroedinger is solved using these PECs plus Born-Oppenheimer and spin splitting correction terms. Line intensities and Einstein A coefficients are computed using ab initio Dipole Moment Curves (DMC) X-X and a-a. The resulting LaTY line list, which contains 65055 transitions for 2528 rovibronic states up to 24500cm^-1^ and J=80, is used to simulate spectra in emission and absorption at a range of temperatures. The line list is made available in electronic form at the CDS and ExoMol databases.
