: While weak H-bonds are primarily electrostatic (dipole-dipole), strong H-bonds exhibit orbital overlap and partial covalent character.
The review outlines how these specific types of hydrogen bonds drive critical chemical and biological processes:
: Strong bonds where π-conjugation enhances the interaction. The Nature of the Hydrogen Bond: Outline of a C...
The book , written by Gastone Gilli and Paola Gilli, provides a modern synthesis of how hydrogen bonds (H-bonds) function beyond simple electrostatic attraction. It addresses the "H-bond puzzle"—the mystery of why O-H...O bond energies can vary wildly from less than 1 to over 30 kcal/mol—by classifying them into six distinct "chemical leitmotifs". Key Pillars of the Theory
: Extremely strong bonds formed when the donor and acceptor are charged. It addresses the "H-bond puzzle"—the mystery of why O-H
: The theory posits that H-bond strength is maximized when the proton affinity (PA) or pKa of the donor and acceptor are matched, creating a "low-barrier" for the proton. Functional Importance
The authors move away from a purely electrostatic view to a "twofold nature" that includes significant covalent contributions, especially in stronger bonds. Functional Importance The authors move away from a
: A core feature of the book is the classification of H-bonds into six categories based on their strength and mechanism, including: