Ab Initio Study of Fine and Hyperfine Interactions in Triplet POH

Phosphorous-containing molecules have a great relevance in prebiotic chemistry in view of the fact that phosphorous is a fundamental constituent of biomolecules, such as RNA, DNA, and ATP. Its biogenic importance has led astrochemists to investigate the possibility that P-bearing species could have formed in the interstellar medium (ISM) and subsequently been delivered to early Earth by rocky bodies. However, only two P-bearing molecules have been detected so far in the ISM, with the chemistry of interstellar phosphorous remaining poorly understood. Here, in order to shed further light on P-carriers in space, we report a theoretical spectroscopic characterisation of the rotational spectrum of POH in its 3A″ ground electronic state. State-of-the-art coupled-cluster schemes have been employed to derive rotational constants, centrifugal distortion terms, and most of the fine and hyperfine interaction parameters, while the electron spin–spin dipolar coupling has been investigated using the multi-configuration self-consistent-field method. The computed spectroscopic parameters have been used to simulate the appearance of triplet POH rotational and ro-vibrational spectra in different conditions, from cold to warm environments, either in gas-phase experiments or in molecular clouds. Finally, we point out that the predicted hyperfine structures represent a key pattern for the recognition of POH in laboratory and interstellar spectra.

Synthesis and Spectroscopy of Buckminsterfullerene Cation C60+ in a Cryogenic Ion Trapping Instrument

The assignment of several diffuse interstellar bands in the near-infrared to C60+ ions present at high abundance in space has renewed interest in the astrochemical importance of fullerenes and analogues. Many of the latter have not been produced in macroscopic quantities, and their spectroscopic properties are not available for comparison with astronomical observations. An apparatus has been constructed that combines laser vaporisation synthesis with spectroscopic characterisation at low temperature in a cryogenic trap. This instrument is used here to record the electronic absorptions of C60+ produced by laser vaporisation of graphite. These are detected by (helium tagged) messenger spectroscopy in a cryogenic trap. By comparison with spectra obtained using a sublimed sample of Buckminsterfullerene, the observed data show that this isomer is the dominant C60+ structure tagged with helium at m/z=724, indicating that the adopted approach can be used to access the spectra of other fullerenes and derivatives of astrochemical interest.

Community Access to CHEOPS

<p>Launched on 18 December 2019, CHEOPS (CHaracterising ExOPlanet Satellite) is the first exoplanet mission dedicated to the search for transits of exoplanets by means of ultrahigh precision photometry of bright stars already known to host planets. It is the first S-(small) class mission in ESA’s Cosmic Vision 2015-2025, and a partnership between Switzerland and ESA, with important contributions from 10 other member states.<br class="" /><br class="" />CHEOPS will provide the unique capability of determining accurate radii for a subset of planets in the super-Earth to Neptune mass range, for which masses have already been estimated from ground- based spectroscopic surveys. It will also provide precision radii for new planets discovered by ground- and space-based transit surveys, including TESS. By combining known masses with CHEOPS sizes, it will be possible to determine accurate densities for these smaller planets, providing key insight into their composition and internal structure. By identifying transiting exoplanets with high potential for in-depth characterisation – e.g. those that are potentially rocky and have thin atmospheres - CHEOPS will also provide prime targets for future instruments suited to the spectroscopic characterisation of exoplanetary atmospheres.</p> <p>In this poster we detail how the Community can access CHEOPS, with emphasis on the ESA-run Guest Observers Programme and the Annual Announcement of Opportunity for observing time Year 3 of CHEOPS, which is foreseen to come out in Quarter 4 2021.</p>

Twinkle: Update on the international, collaborative exoplanet survey

<div>The Twinkle Space Mission is a space-based observatory that has been conceived to measure the atmospheric composition of exoplanets, stars and solar system objects. Twinkle’s collaborative multi-year global survey programmes will deliver visible and infrared spectroscopy of thousands of objects within and beyond our solar system, enabling participating scientists to produce world-leading research in planetary and exoplanetary science. Twinkle’s growing group of international Founding Members have now started shaping the survey science programme within focused Science Teams and Working Groups and will soon be delivering their first papers.</div> <div> </div> <div>Twinkle will have the capability to provide simultaneous broadband spectroscopic characterisation (0.5 - 4.5µm) of the atmospheres of several hundred bright exoplanets, covering a wide range of planetary types. It will also be capable of providing phase curves for hot, short-period planets around bright stars targets and of providing ultra-precise photometric light curves to accurately constrain orbital parameters, including ephemerides and TTVs/TDVs present in multi-planet systems.<br /><br />I will present an overview of Twinkle’s mission status and discuss some example exoplanet surveys to highlight the broad range of targets the mission could observe, demonstrating the scientific potential of the spacecraft. I will also report on the work of the Twinkle exoplanet Science Team, showcasing their science interests and the studies into Twinkle’s capabilities that they have conducted since joining the mission.</div>

1st Row Transition Metal Aluminylene Complexes: Preparation, Properties and Bonding Analysis

<i>The synthesis and spectroscopic characterisation of eight new first-row transition metal (M = Cr, Mn, Fe, Co, Cu) aluminylene complexes is reported. DFT and ab<b> </b>initio calculations have been used to provide detailed insight into the metal–metal bond. The σ-donation and π-backdonation properties of the aluminylene ligand are evaluated via NBO and ETS-NOCV calculations. These calculations reveal that these ligands are strong σ-donors but also competent π-acceptors. These properties are not fixed but vary in response to the nature of the transition metal centre, suggesting that aluminylene fragments can modulate their bonding to accommodate both electron-rich and electron-poor transition metals. Ab initio<b> </b>DLPNO-CCSD(T) calculations show that dispersion plays an important role in stabilising these complexes. Both short-range and long-range dispersion interactions are identified. These results will likely inform the design of next-generation catalysts based on aluminium metalloligands. </i>

1st Row Transition Metal Aluminylene Complexes: Preparation, Properties and Bonding Analysis

<i>The synthesis and spectroscopic characterisation of eight new first-row transition metal (M = Cr, Mn, Fe, Co, Cu) aluminylene complexes is reported. DFT and ab<b> </b>initio calculations have been used to provide detailed insight into the metal–metal bond. The σ-donation and π-backdonation properties of the aluminylene ligand are evaluated via NBO and ETS-NOCV calculations. These calculations reveal that these ligands are strong σ-donors but also competent π-acceptors. These properties are not fixed but vary in response to the nature of the transition metal centre, suggesting that aluminylene fragments can modulate their bonding to accommodate both electron-rich and electron-poor transition metals. Ab initio<b> </b>DLPNO-CCSD(T) calculations show that dispersion plays an important role in stabilising these complexes. Both short-range and long-range dispersion interactions are identified. These results will likely inform the design of next-generation catalysts based on aluminium metalloligands. </i>