The H₂S Dimer is Hydrogen‐Bonded: Direct Confirmation from Microwave Spectroscopy

Abstract

Ice and solid H2S look as different as pears and oranges, leading Pauling to conclude that H2O has hydrogen bonds and H2S has van der Waals interactions. Now it is shown that the H2S dimer, like the H2O dimer, is indeed hydrogen‐bonded.

Biocompatible metal–organic frameworks for the storage and therapeutic delivery of hydrogen sulfide

“…Additional hydrogen-bonding interactions between adjacent H 2 S molecules are predicted, with S–H⋯S distances ranging from 2.38 Å to 2.54 Å. Notably, these distances are slightly shorter than the S–H⋯S distance in (H 2 S) 2 (2.78 Å), 34 likely due to the increased polarization of H 2 S molecules interacting with the framework pores. The favorable packing of H 2 S within the tetrahedral cavities accounts for its strong yet reversible adsorption in all three frameworks.…”

“…77 K N2 adsorption isotherms of activated Zr-fum-H2O, Zr-mes-H2O, and Zr-ita-H2O before (blue) and after treatment with H2S at 25 °C (red). After H2S adsorption, the MOFs were regenerated at 100 °C under vacuum (<10 μbar) for 48 h. 34 likely due to the increased polarization of H2S molecules interacting with the framework pores. The favorable packing of H2S within the tetrahedral cavities accounts for its strong yet reversible adsorption in all three frameworks.…”

“…A promising strategy to identify new MOFs capable of reversibly adsorbing H2S is to leverage its properties as a hydrogen-bond donor and weak hydrogen-bond acceptor, similar to water. 34 As such, we were inspired by the recent deluge of MOFs designed for reversible water capture [35][36][37][38] to identify potential frameworks for H2S storage. In particular, we hypothesized that the surprisingly strong binding of water (−ΔHads ≈ 60 kJ/mol) in Zr6O4(OH)4(fumarate)6 or MOF-801 (Figure 1, left), which is due to ordered hydrogen-bonding interactions within the tetrahedral cavities, 39 may translate to strong binding of H2S within this MOF as well.…”

The Characteristics of Disulfide‐Centered Hydrogen Bonds

“…The intrinsic nature of the NCIs occurring in the clusters are characterized by energy decomposition with symmetryadapted perturbation theory (SAPT) [29] approach. SAPT2 + (3)dMP2/aug-cc-pVDZ [30] results for the three observed structures (Table S21) are graphically represented in Figure 3 and compared to (H 2 O) 2 [31] and (H 2 S) 2 [32] dimers. The total interaction energies (E t ) are estimated to be À17.…”

Vibrational study in neon matrix of H2S-H2O, H2S-(H2O)2, and (H2S)2-H2O complexes. Identification of the two isomers: HOH-SH2 (H2O proton donor) and HSH-OH2 (H2S proton donor)

“…Very recently, a gas phase study of the H 2 S dimer gives the vibrational frequencies  1 and  3 for each proton acceptor and proton donor 24 , and a microwave study shows that the dimer is indeed hydrogen bonded. 25 For the heterocomplex H 2 S-H 2 O, experimental studies exist in solid N 2 26 , Ar 27 , Kr, and Xe 16 , none in gas phase, and vibrational data are often incomplete. Vibrational theoretical studies were performed on the H 2 S monomer and dimer and on the H 2 S-H 2 O complex at MP2 and CCSD(T) level.…”