That is you got the dianion of the mollykewell cyclo-octatetraene as shown...
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This has EIGHT pi"-electrons" and is formally anti-aromatic..(i.e. it does not fulfil the Huckel criteria for aromaticity...) In order to avoid this unfavourable condition..the ring buckles to give a so-called tub shape...
However, the ring can be READILY reduced...by two equiv of alkali metal to give a formal dianion....with "10 pi "electrons"...i.e. C_8H_8^(2-)...cyclo-octatetraenyl dianion... Such an electronic structure fulfils the Huckel criterion, and this beast is planar and aromatic, and has an extensive coordination chemistry...especially with larger metals...
This is the "uranium(IV) derivative", so-called "uranocene"...the uranium analogue of ferrocene..., i.e. [U(eta^8-C_8H_8)_2]
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The C-C bond lengths are all equivalent, and intermediate between C-C, 1.54xx10^-10*m, and C=C, 1.34xx10^-10*m....
