The implications of an electronic coupling model in high T(c) supercon
ductors of YBCO are discussed in which the pairing mechanism is based
upon the ionic bonding. Specifically, the bonding reaction Cu + O reve
rsible Cu++ + O-- resonates at a frequency of I/2piHBAR in the CuO pla
nes, where I = 0.4 eV is the ionic bonding energy. We formulate an Ham
iltonian which allows for the reduction of the total energy by I each
time two holes or two electrons form a pair. The total energy consists
of kinetic energy calculable from band theory, and the ionic bonding
energy proportional to I. We calculate (i) the effective Ginzburg-Land
au free energy for all T < T(c), (ii) the energy gap, (iii) the anisot
ropic London penetration depths, and (iv) the anisotropic coherence le
ngths. General agreement is found between our calculations and experim
ental data.