Editing Thiol (section)

== Structure and bonding ==
Thiols having the structure R−SH, in which an [[alkyl]] group (R) is attached to a [[sulfhydryl]] group (SH), are referred to as ''alkanethiols'' or ''alkyl thiols''.<ref>{{cite web |title=Alkanethiols |url=https://www.rsc.org/publishing/journals/prospect/ontology.asp?id=CHEBI:47908&MSID=c000442a |publisher=[[Royal Society of Chemistry]] |access-date=4 September 2019 }}</ref> Thiols and alcohols have similar connectivity. Because sulfur atoms are larger than oxygen atoms, C−S [[bond length]]s—typically around 180 [[Picometre|picometres]]—are about 40 picometers longer than typical C−O bonds. The C−S−H angles approach 90° whereas the angle for the C−O−H group is more obtuse. In solids and liquids, the [[hydrogen-bonding]] between individual thiol groups is weak, the main cohesive force being [[Van der Waals interaction]]s between the highly polarizable divalent sulfur centers.

The S−H bond is much weaker than the O−H bond as reflected in their respective [[bond dissociation energy|bond dissociation energies]] (BDE). For CH<sub>3</sub>S−H, the BDE is {{cvt|366|kJ/mol|kcal/mol}}, while for CH<sub>3</sub>O−H, the BDE is {{cvt|440|kJ/mol|kcal/mol}}.<ref>{{RubberBible87th}}</ref>

An S−H bond is moderately [[Chemical polarity|polar]] because of the small difference in the [[electronegativity]] of sulfur and hydrogen. In contrast, O−H bonds in hydroxyl groups are more polar. Thiols have a lower [[Bond dipole moment|dipole moment]] relative to their corresponding alcohols.