Abstract: This paper caculated the highly excited states with J=2 and odd parity of the beryllium isoelectronic sequence by using the eigenchannel quantum defect theory (EQDT).It obtained the EQDT parameters U_iα and μ_α,of Be like systems from BeⅠ to OⅤ,as functions of effective nuclear charge.These results indicate that the differences between eigenquantum defects of different channels,which characterize the channel interactions,gradually diminish along this sequence.This isoelectronic behaviour is caused by the competition between electronic and spin orbit interaction along the evaluated with EQDT parameters as input.As a numerical example,the Lu Fano plots of BeⅠ is given as wall.

Key words: beryllium isoelectronic sequence, highly excited state, eigenchannel quantum defect theory