Letters: July 2026

Pauling’s paradigm not at large

I read with interest the article ‘Molecules with largest dipole moments aren’t due to electronegativity differences’, which notes that ‘some of the trends seen in diatomics may not translate directly to more complex chemistry’.

One familiar trend in diatomics is that homonuclear molecules have no dipole moment. That trend can be violated strikingly in larger homonuclear molecules, as shown in ‘Partial ionic character beyond the Pauling paradigm: metal nanoparticles’.