Potential Energy Surface of SOCl₃^-

Abstract

Sulfur trichloride monoxide anion (SOCl 3 -) is stable in the gas phase. The G2 estimate of the energy for its dissociation to thionyl chloride and chloride anion is 102.8 kJ mol -1 . The potential energy surface for the reaction SOCl 2 + Clf SOCl 3has just a single well corresponding to the product. Collision-induced dissociation observed using a flowing afterglow-tandem mass spectrometer indicates a D 0 (SOCl 2 -Cl -) bond energy of 85.4 ( 7.6 kJ mol -1 , which is very similar to the previously determined bond energy D 0 (SCl 2 -Cl -) ) 85 kJ mol -1 .

Bond Strengths in ChCl3-and ChOCl3-(Ch = S, Se, Te): Experiment and Theory

“…It was previously noted that the oxygen atom in SOCl 2 does not assist in delocalizing the negative charge when Clis added to the molecule. 2 This is also true for SeOCl 2 and TeOCl 2 . It is possible that the relatively small electrostatic bond strength increase is canceled for Ch ) S by increased ligand-ligand repulsions, which are smaller for the larger chalcogens Se and Te.…”

“…This same shape was observed for the potential energy surfaces for the reaction of chloride with SCl 2 or SOCl 2 . 1,2 In all of these examples, a stable hypercoordinate sulfur or selenium anion can be created when suitably substituted with electron-withdrawing groups that stabilize the anionic charge. This is consistent with an addition-elimination nucleophilic substitution mechanism for attack at the chalcogens.…”

“…The addition-elimination mechanism also holds for nucleophilic substitution at selenium in simple diselenides and selenosulfides. 20 Our earlier studies 1,2 of SCl 3and SOCl 3were motivated by the desire to dramatically stabilize the hypercoordinate intermediate on the addition-elimination pathway. The same motivation applies here: can placement of electronwithdrawing groups on selenium or tellurium lead to a very stable hypercoordinate intermediate?…”

“…We have recently performed experimental measurements and computational studies of the bond strengths in the hypervalent anions SCl 3 - and SOCl 3 - . , These anions are termed hypervalent − (or hypercoordinate) because their electron dot structures show 10 electrons around the sulfur atom. Although these anions violate the octet rule, the bonds are reasonably strong: D(SCl 2 −Cl - ) and D(SOCl 2 −Cl - ) are both 85 ± 8 kJ mol -1 . , …”

The Role of Additives in the Electroreduction of Sodium Ions in Chloroaluminate-Based Ionic Liquids

“…HCl acts similarly to provide more freedom to the Na ϩ ion. Thus, SOCl 2 and HCl act as a Lewis acids [16][17][18] and compete with AlCl 3 for Cl Ϫ . Na ϩ dissociation ͑as measured by conductivity and deposition of Na metal͒ may also be achieved in these melts without the addition of a new chemical by carrying out the oxidation of the melt producing chlorine from the chloride-containing species.…”