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The simplest diphosphene HPPH and isomeric diphosphinyldene PPH2 features prototype phosphorus‐phosphorus multiple bonding properties that have been of long‐standing interest in main‐group chemistry. Herein, we report the observation of cis‐HPPH, trans‐HPPH, and PPH2 among the respective laser photolysis products of phosphine (PH3) and diphosphine (P2H4) in solid N2‐ and Ar‐matrices at 10 K. The identification of these P2H2 isomers with matrix‐isolation IR and UV/Vis spectroscopy is supported by D‐isotope labeling and the quantum chemical calculations at the CCSD(T)‐F12a/cc‐pVTZ‐F12 level using configuration‐selective vibrational configuration interaction theory (VCI). Bonding analyses suggest that the two conformers of HPPH contain standard PP double bonds, whereas, PPH2 resembles P2 in having partial PP triple bond due to the H2P←P π bonding interaction. [ABSTRACT FROM AUTHOR]

The simplest diphosphene HPPH and isomeric diphosphinyldene PPH2 features prototype phosphorus‐phosphorus multiple bonding properties that have been of long‐standing interest in main‐group chemistry. Herein, we report the observation of cis‐HPPH, trans‐HPPH, and PPH2 among the respective laser photolysis products of phosphine (PH3) and diphosphine (P2H4) in solid N2‐ and Ar‐matrices at 10 K. The identification of these P2H2 isomers with matrix‐isolation IR and UV/Vis spectroscopy is supported by D‐isotope labeling and the quantum chemical calculations at the CCSD(T)‐F12a/cc‐pVTZ‐F12 level using configuration‐selective vibrational configuration interaction theory (VCI). Bonding analyses suggest that the two conformers of HPPH contain standard PP double bonds, whereas, PPH2 resembles P2 in having partial PP triple bond due to the H2P←P π bonding interaction. [ABSTRACT FROM AUTHOR]

The carbon suboxide anion C3O2− is generated in solid neon matrix. It is characterized by infrared absorption spectroscopy as well as quantum chemical calculations to have a planar Cs structure where two CO groups with significantly different bond lengths and angles are attached in a zigzag fashion to the central carbon atom. Bonding analysis indicates that it is best described by the bonding interactions between a neutral CO in a triplet excited state and a doublet excited state of CCO−. [ABSTRACT FROM AUTHOR]

Smart molecular crystals with light‐driven mechanical responses have received interest owing to their potential uses in molecular machines, artificial muscles, and biomimetics. However, challenges remain in control over both the dynamic photo‐mechanical behaviors and static photonic properties of molecular crystals based on the same molecule. Herein, we show the construction of isostructural co‐crystals allows their light‐induced cracking and jumping behaviors (photosalient effect) to be controlled. Hydrogen‐bonded co‐crystals from 4‐(1‐naphthylvinyl)pyridine (NVP) with co‐formers (tetrafluoro‐4‐hydroxybenzoic acid (THA) and tetrafluorobenzoic acid (TA)) crystallize as isostructural crystals, but have different static and dynamic photo‐mechanical behaviors. These differences are due to alternations in the orientation of NVP and hydrogen‐bonding modes of the co‐formers. After light activation, the 1D NVP‐TA crystal splits and shears off within 1 s. For NVP‐THA, its photostability and high quantum yield give novel photonic properties, including low optical waveguide loss, highly polarized anisotropy, and efficient up‐conversion fluorescence. [ABSTRACT FROM AUTHOR]

Phosphorus monoxide (.PO) is a key intermediate in phosphorus chemistry, and its association with the hydroxyl radical (.OH) to yield metaphosphorous acid (cis‐HOPO) contributes to the chemiluminescence in the combustion of phosphines. When photolyzing cis‐HOPO in an Ar‐matrix at 2.8 K, the simplest dioxophosphorane HPO2 and an elusive hydroxyl radical complex (HRC) of.PO form. This prototypical radical‐radical complex reforms into cis‐HOPO at above 12.0 K by overcoming a barrier of 0.28±0.02 kcal mol−1. The vibrational spectra of this HRC and its D‐ and 18O‐isotopologues suggest a structure of.OH⋅⋅⋅OP. for which a triplet spin multiplicity with a binding energy of −3.20 kcal mol−1 has been computed at the UCCSD(T)‐F12a/aug‐cc‐pVTZ level. [ABSTRACT FROM AUTHOR]

Alkynyl isocyanates have been postulated as highly reactive intermediates in synthetic chemistry. Herein, the parent molecule HC≡CNCO is isolated for the first time. In sharp contrast to the previously reported short lifetime (ca. 15 s) at room temperature, we found that HC≡CNCO has a lifetime of 55 h in the gas phase (2 mbar, 300 K) with a melting point of −79.5 °C and vaporization enthalpy (ΔHvap) of 23.1(1) kJ mol−1. Apart from the IR (gas, solid, and matrix), 1H and 13C NMR, and UV/Vis spectroscopic characterization, its photoisomerization with a acylnitrene HC≡CC(O)N and cyanoketene NCC(H)CO has been observed. [ABSTRACT FROM AUTHOR]

Extensive applications for photodetectors have led to demand for high‐responsivity polarization‐sensitive light detection. Inspired by the elaborate architecture of butterfly Papilio paris, a 1D nanograting bonded porous 2D photonic crystal perovskite photodetector (G‐PC‐PD) using a commercial DVD master and 2D crystalline colloidal arrays template was fabricated. The coupling effect from grating diffraction and reflection of the PC stopband renders the enhanced light harvesting of G‐PC‐PD. The porous scaffold and nanoimprinting process afford a highly crystalline perovskite film. White light responsivity and detectivity of G‐PC‐PD are up to 12.67 A W−1 and 3.22×1013 Jones (6∼7 times that of a pristine perovskite photodetector). The highly ordered nanograting arrays of G‐PC‐PD enable polarization‐sensitive light detection with a rate of −0.72 nA deg−1. This hierarchical perovskite integrated nanograting and 2D PC architecture opens a new avenue to high‐performance optoelectronic devices. [ABSTRACT FROM AUTHOR]

Methoxyphosphinidene oxide (CH3OPO) and isomeric methyldioxophosphorane (CH3PO2) are key intermediates in the degradation of organophosphorus compounds (OPCs). Unlike the nitrogen analogues CH3ONO and CH3NO2, the experimental data for these two prototypical OPCs are scarce. By high‐vacuum flash pyrolysis (HVFP) of the diazide CH3OP(O)(N3)2 at 1000 K, the cis and trans conformers of CH3OPO have been generated in the gas phase and subsequently isolated in cryogenic Ar and N2 matrices for IR spectroscopic characterization. Upon 266 nm laser irradiation of CH3OPO, cis→trans conformational conversion occurs with concurrent isomerization to CH3PO2. The spectroscopic identification of CH3OPO and CH3PO2 is supported by D‐, 13C‐, and 18O‐isotope labeling and quantum chemical calculations at the CCSD(T)‐F12a/cc‐pVTZ‐F12 level using configuration‐selective vibrational configuration interaction (VCI). [ABSTRACT FROM AUTHOR]

Abstract: The simplest aminosulfinyl radical H2NSO has been generated in the gas phase through flash vacuum pyrolysis of CF3S(O)NH2 at approximately 1000 K. Upon UV light irradiation (365 nm), 1,3‐H migration occurs in H2NSO and furnishes an elusive N‐amidyl radical HNSOH in syn and anti conformations in cryogenic matrices (N2 or Ar, 15 K). Further 266 nm laser irradiation results in dissociation of HNSOH to H2O and SN and concomitant reformation of H2NSO in trace amount. The identification of H2NSO, syn‐HNSOH, and anti‐HNSOH by matrix‐isolation IR spectroscopy is supported by high‐level quantum chemical computations. [ABSTRACT FROM AUTHOR]

Methoxyphosphinidene oxide (CH3OPO) and isomeric methyldioxophosphorane (CH3PO2) are key intermediates in the degradation of organophosphorus compounds (OPCs). Unlike the nitrogen analogues CH3ONO and CH3NO2, the experimental data for these two prototypical OPCs are scarce. By high‐vacuum flash pyrolysis (HVFP) of the diazide CH3OP(O)(N3)2 at 1000 K, the cis and trans conformers of CH3OPO have been generated in the gas phase and subsequently isolated in cryogenic Ar and N2 matrices for IR spectroscopic characterization. Upon 266 nm laser irradiation of CH3OPO, cis→trans conformational conversion occurs with concurrent isomerization to CH3PO2. The spectroscopic identification of CH3OPO and CH3PO2 is supported by D‐, 13C‐, and 18O‐isotope labeling and quantum chemical calculations at the CCSD(T)‐F12a/cc‐pVTZ‐F12 level using configuration‐selective vibrational configuration interaction (VCI). [ABSTRACT FROM AUTHOR]