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Abstract We present the spectroscopic characterization of cyclopropenethione in the laboratory and detect it in space using the Green Bank Telescope Observations of TMC-1: Hunting Aromatic Molecules survey. The detection of this molecule—the missing link in understanding the C3H2S isomeric family in TMC-1—completes the detection of all three low-energy isomers of C3H2S, as both CH2CCS and HCCCHS have been previously detected in this source. The total column density of this molecule (NTof cm−2at an excitation temperature of K) is smaller than both CH2CCS and HCCCHS and follows nicely the relative dipole principle (RDP), a kinetic rule of thumb for predicting isomer abundances that suggests that, all other chemistry among a family of isomers being the same, the member with the smallest dipole (μ) should be the most abundant. The RDP now holds for the astronomical abundance ratios of both the S-bearing and O-bearing counterparts observed in TMC-1; however, CH2CCO continues to elude detection in any astronomical source.
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Molecular Mimics of Heterogeneous Metal Phosphides: Thermochemistry, Hydride‐Proton Isomerism, and HER Reactivity
Abstract A new series of low‐valent dinuclear molybdenum complexes bearing phosphido or phosphinidene bridging ligands was synthesized as a structural model of heterogeneous metal phosphide catalysts. Addition of acid to a monocationic Mo2‐μ‐P complex results in phosphide protonation, affording a dicationic Mo2‐μ‐PH species. Alternatively, reaction of an isoelectronic Mo2‐μ‐P precursor with LiBEt3H gives a Mo2H‐μ‐P complex. Mixing these species, one bearing a Mo−H and the other a P−H bond, results in facile H2production at room temperature.
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- Award ID(s):
- 1800501
- PAR ID:
- 10079492
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Angewandte Chemie International Edition
- Volume:
- 57
- Issue:
- 50
- ISSN:
- 1433-7851
- Page Range / eLocation ID:
- p. 16329-16333
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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