Elusive Sulfurous Acid: Gas-Phase Basicity and IR Signature of the Protonated Species.
The ion corresponding to protonated sulfurous acid, H3SO3(+), has been successfully delivered into the gas phase by electrospray ionization of the solution of a suitable precursor and an in-source fragmentation process. The neutral acid is a highly elusive molecule. However, its gas-phase basicity has been ascertained by means of a kinetic study of proton-transfer reactivity. The structure of the H3SO3(+) sampled ion has been probed by IRMPD spectroscopy in two complementary IR frequency ranges in conjunction with density functional theory calculations and found to conform to a trihydroxosulfonium ion. The characteristic IR signatures may aid in deciphering the presence of this species in extraterrestrial atmospheres.
†Faculté des Sciences, Laboratoire de Chimie Physique, UMR8000 CNRS, Université Paris-Sud, Batiment 349, 91405 Orsay Cedex, France.|∥Department of Atomic and Molecular Physics, Manipal University, Manipal, 576104 Karnataka, India.
Rajeev K
RK
Sinha
†Faculté des Sciences, Laboratoire de Chimie Physique, UMR8000 CNRS, Université Paris-Sud, Batiment 349, 91405 Orsay Cedex, France.
Debora
D
Scuderi
†Faculté des Sciences, Laboratoire de Chimie Physique, UMR8000 CNRS, Université Paris-Sud, Batiment 349, 91405 Orsay Cedex, France.
Philippe
P
Maitre
‡Dipartimento di Chimica e Tecnologie del Farmaco, Università di Roma "La Sapienza", P.le A. Moro 5, 00185 Roma, Italy.
Barbara
B
Chiavarino
‡Dipartimento di Chimica e Tecnologie del Farmaco, Università di Roma "La Sapienza", P.le A. Moro 5, 00185 Roma, Italy.
Maria Elisa
ME
Crestoni
‡Dipartimento di Chimica e Tecnologie del Farmaco, Università di Roma "La Sapienza", P.le A. Moro 5, 00185 Roma, Italy.
Simonetta
S
Fornarini
IRMPD spectroscopy; density functional theory calculations; gas-phase ion chemistry; inorganic cations; mass spectrometry; molecular structure; planet atmosphere