= Solution
\b[F$_2$ is an eight-membered ring with sequence $\mathrm{Cu-N-Li-C_{ipso}-Cu-N-Li-C_{ipso}}$], closed back to the first Cu. Each N belongs to TMP; each ipso carbon belongs to a phenyl group. Each Cu is approximately linear between one TMP nitrogen and one phenyl ipso carbon. Each Li contacts a TMP nitrogen and the phenyl group bound to the other Cu, so the dimer is assembled head-to-tail rather than from two independent separated ion pairs.
\b[G has the eight-membered sequence $\mathrm{Cu_1-N_1-Li_2-N_2-Cu_3-N_3-Li_4-C_{ipso}}$], closed to Cu$_1$. The three N atoms belong to three TMP groups and the carbon belongs to the single phenyl group. Both copper sites remain approximately two-coordinate. The Li next to phenyl can also interact with its aromatic $\pi$ surface; this secondary contact need not have the same hapticity as in F$_2$. The figure gives a connectivity projection, not idealized square bond angles or an X-ray metric reconstruction.
\Image[/past-exam-of-the-chemistry-course-of-the-year-4-of-the-natural-sciences-course-of-the-university-of-cambridge/2022/paper-2-amidometal-aggregates.png]
{title=Original connectivity diagrams for amido-metal aggregates and the exchangeable lithium-amide segment}
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