Low‐Temperature Thermal Formation of the Cyclic Methylphosphonic Acid Trimer [c‐(CH₃PO₂)₃]

Abstract

We report the formation of the cyclic methylphosphonic acid trimer [c-(CH 3 PO 2 ) 3 ] through condensation reactions during thermal processing of low-temperature methylphosphonic acid samples exploiting photoionization reflectron time-of-flight mass spectrometry (PIÀ ReTOFÀ MS) along with electronic structure calculations. Cyclic methylphosphonic acid trimers are formed in the solid state and detected together with its protonated species in the gas phase upon single photon ionization. Our studies provide an understanding of the preparation of phosphorus-bearing potentially prebiotic molecules and the fundamental knowledge of low-temperature phosphorus chemistry in extraterrestrial environments.

Interstellar formation of glyceric acid [HOCH 2 CH(OH)COOH]—The simplest sugar acid

“…The CCSD(T)-F12b/cc-pVTZ-F12 single-point energy of PBE0/aug-cc-pVTZ and ωB97XD/aug-cc-pVTZ anharmonic vibrational analysis for both density functionals were calculated for 1 and 18 ; the shifts in IE and relative energy are shown in table S8. This approach has demonstrated a good correlation with experiments in previous work ( 72 ). The computed Cartesian coordinates and harmonic and anharmonic vibrational frequencies are listed in table S9.…”

Quantum Chemistry and Astrochemistry: A Match Made in the Heavens

“…The oft-vaunted “chemical accuracy” of sub-1.0 kcal mol –1 or, even better for non-Americans, sub-1.0 kJ mol –1 has been well-surpassed in quantum chemistry largely since the advent of coupled cluster theory within its singles, doubles, and perturbative triples [CCSD­(T)] incarnation more than 30 years ago. − This is especially true in collusion with correlation consistent basis sets , labeling CCSD­(T)/aug-cc-pVTZ as the “gold standard” of quantum chemistry . Again, application to gas phase or nearly truly isolated chemical reactions like those in the ISM is a perfect fit rendering reaction profiles computed at this level quantitatively insightful. , Additionally, other observables such as ionization potentials and relative energies are readily produced to within 1% or better of experiment which is good enough to compare to observations from a controlled laboratory environment. ,, The advent of explicit correlation in the F12 variants − has allowed triple-ζ-level basis sets to function as quintuple-ζ basis sets precluding the need for costly complete basis set extrapolations in determining such observables to “chemical accuracy,” whether defined by the user as 1.0 kcal mol –1 or 1.0 kJ mol –1 . , Even CCSD­(T)-F12b/cc-pVTZ-F12 single point energies upon DFT optimized geometries for larger molecules are more than accurate enough for clear correlation between theory and experiment for simulated astrochemical conditions . Hence, modern quantum chemistry provides sufficient accuracy for direct correlation to any gas phase physical observable, whether for astrochemical applications or otherwise, where accuracies are needed on the sub-1.0 kJ mol –1 level.…”

“…53,54 Even CCSD(T)-F12b/cc-pVTZ-F12 single point energies upon DFT optimized geometries for larger molecules are more than accurate enough for clear correlation between theory and experiment for simulated astrochemical conditions. 55 Hence, modern quantum chemistry provides sufficient accuracy for direct correlation to any gas phase physical observable, whether for astrochemical applications or otherwise, where accuracies are needed on the sub-1.0 kJ mol −1 level. Other needed physical parameters for astrochemistry, however, need greater accuracy than this.…”

Pyrophosphonate Covalent Organic Frameworks

“…For example, there are a few reports about the ab initio calculations studying the condensation of phosphinic acids and methylphosphonic acid to provide geometry and reaction energies to form dimers, trimers, tetramers and cyclization. 24,25 There are also limited experimental reports in the literature reporting the condensation of phosphonic acid to form dimers. For example, a proton-conducting polymer poly(vinyl phosphonic acid) is known to condense forming dimers at higher temperatures, which limits its proton-conducting ability.…”