LBHB
Low-barrier hydrogen bonds (LBHBs) are a type of hydrogen bond in which the proton is shared almost equally between two electronegative atoms, typically oxygen or nitrogen, creating an unusually short and strong interaction. The concept arises when the donor and acceptor have closely matched pKa values, leading to a shallow or almost single-well potential for proton position and allowing quantum delocalization of the proton across the two centers.
LBHBs are typically characterized by very short donor–acceptor distances, often around 2.5 Å or less, and by
In biochemistry and enzymology, LBHBs have been proposed as a mechanism to stabilize transition states or facilitate
Critics argue that many claims can be explained by conventional strong hydrogen bonds with short distances