hydrogen bond

A weak bond in which a proton (H⁺) is shared between two other atoms. The atom to which the proton is more tightly linked is called the hydrogen donor. The other atom is the acceptor. The acceptor has an unshared pair of electrons to share with the proton. Hydrogen bonds may be formed between charged or uncharged molecules. / / Examples include: N-H ... O=C O-H ... O / Typical hydrogen bond lengths: Bond Length (anstroms) O-H ... O 2.70 O-H ... O 2.63 O-H ... N 2.88 N-H ... O 3.04 +N-H ... O 2.93 N-H ... N 3.10

References

Biochemistry, L. Stryer, WH Freeman & Co, New York, 1988 pg 7