Rotational spectrum of anisole-CO2: Cooperative C···O tetrel bond and C H···O hydrogen bond

Conformational equilibria in acrolein–CO2: the crucial contribution of n → π* interactions unveiled by rotational spectroscopy

“…8 There has been a rigorous effort to qualitatively and quantitatively decipher the non-covalent interactions (NCIs) between CO 2 and partner molecules, through rotational spectroscopic investigations complemented by quantum chemical calculations. [9][10][11][12][13][14][15][16][17][18][19][20] In complexes with strong proton donors such as HF 9 and HCl, 10 CO 2 is predominantly involved in F/Cl-HÁ Á ÁOQC hydrogen bonds (HBs) within a linear form. Complexes formed with carboxylic acids (formic acid 11 and acrylic acid 12 ), which also act as strong proton donors, whose complexes with CO 2 , indeed, are stabilized by pronounced O-HÁ Á ÁOQC HBs.…”

“…In addition, the carbonyl group in the carboxylic acids can serve as the electron donor, engaging with the p-hole of CO 2 to form a secondary CÁ Á ÁO tetrel bond (TB). Conversely, CO 2 tends to form a primary CÁ Á ÁCl/F/N/O/S TB in its interactions with nucleophilic molecules, as found in complexes with chlorotrifluoromethane, 13 trifluoroethylene, 14 pyridine, 15 anisole, 16 phenol, 17 and phenyl isothiocyanate. 18 The intricate dynamics of competition and cooperation between HBs and TBs play a pivotal role in maintaining the conformational integrity of CO 2 complexes.…”

CO2Aggregation on Monoethanolamine: Observations from Rotational Spectroscopy

“…[20] Recently, insights into noncovalent interactions between CO 2 and complex partner molecules containing various func-tional groups including NH 2 , OH, C=O, ether, and aryl were systematically gained via rotational spectroscopy. [21] In this study, we present the direct observation of subnanometer scale CO 2 aggregation processes on MEA using broadband chirped-pulse Fourier transform microwave (CP-FTMW) spectroscopy, also known as Molecular Rotational Resonance spectroscopy [22] combined with high-level theoretical calculations. An interesting competition between the MEA intramolecular hydrogen bond (H-bond) and the intermolecular interactions between MEA and CO 2 upon cluster growth was discovered revealing the aggregation pattern of early-stage gas-phase nucleation.…”

C···S Tetrel Bond Favored in the Phenyl Isothiocyanate-CO2 Complex: A Rotational Study

“…With formic acid and acrylic acid, a primary O–H···OC HB interaction and a secondary OC (CO2) ···OC (acid) TB interaction are found to characterize the resulting CO 2 complexes. However, CO 2 links with formaldehyde, propylene oxide, ethylene oxide, methanol, acetophenone, benzaldehyde, anisole, phenol, formamide, isopropylamine, and 1,1-difluoroethylene through a dominant interaction as the C···O/N/F TB. In addition, the secondary C–H···OC HB also plays a role in determining their stabilities.…”