Research

Research

Disulfuric acid dissociated by two water

  • POSTED DATE : 2015-11-02
  • WRITER :
  • HIT : 3378
  • Researcher : Seong Kyu Kim*

 

 

 

Computational research from the Center of Superfunctional
Materials of Profs. Seong Kyu Kim and Kwang S. Kim at
Sungkyunkwan University and Ulsan National Institute of
Science and Technology (UNIST), Korea.
Title: Disulfuric acid dissociated by two water molecules: ab
initio and density functional theory calculations
Superacid H2S2O7 sets a new record for the fewest number of
water molecules to induce acid dissociation; it is only two! It is
attributed to its unique structure with S–O–S torsional fl exibilities
for many polarizable sulfonyl groups. The fi rst water forming
double donating H-bonds with two sulfonyl groups forms an
additional accepting H-bond with the second water which forms
a donating H-bond with another sulfonyl group. These strong
triple H-bonds of the fi rst water assisted by the relayed H-bonds
of the second water greatly stabilize the formation of H3O+ by the
transfer of H+ from H2S2O7 to the fi rst water. The fewest number
reported so far was three for HClO4
–.