The bond length in a molecule is dependent on bond order The higher is the bond order smaller will be the bond length Peroxide ion `O_(2)^(2)`
`O_(2)^(2-):KK^(**) (sigma 2s)^(2) (sigma^(**)2s)(sigma2p_(z))^(2) (pi 2p_(x))^(2) (pi2p_(y))^(2)`
`(pi^(**)2p_(x))^(2) (sigma^(**)2p_(y))^(2)`
Bond order `= (10-8)/(2) =1`
Superoxide ion, `O_(2)^(Θ)`
`O_(2)^(Theta:KK^(**)) (sigma2s)^(2) (sigma^(**2s))^(2) (sigma2p_(z))^(2) (pi 2p_(z))^(2) (pi 2p_(y))^(2)`
`(pi^(**)2px)^(2)(pi^(**)2p_(y))^(1)`
Bond order `= (10-7)/(2) = 1.5`
Bond order of superoxide ion is higher thajn peorxide ion hence bond lenght of peroxide ion is larger .
