  To describe pseudogap regime in Bi2212 we employ novel generalized ab initio
LDA+DMFT+Sigma_k hybrid scheme. This scheme is based on the strategy of one of
the most powerfull computational tool for real correlated materials LDA+DMFT.
Here the LDA+DMFT equations are supplied by an additional (momentum dependent)
self-energy Sigma_k in the spirit of our recently proposed DMFT+Sigma_k
approach, accounting for pseudogap fluctuations. In the present model Sigma_k
describes non-local correlations induced by short-ranged collective
Heisenberg-like antiferromagnetic spin fluctuations. The effective single
impurity problem of the DMFT is solved by NRG. Material specific model
parameters for effective x2-y2 orbital of Cu-3d shell of Bi2212 compound, e.g.
hopping integrals, local Coulomb interaction U and pseudogap potential Delta
were obtained within LDA and LDA+DMFT. We report theoretical LDA+DMFT+Sigma_k
quasiparticle bands dispersion and damping, Fermi surface renormalization,
momentum anisotropy of (quasi) static scattering, densities of states, spectral
densities and angular resolved photoemission (ARPES) spectra accounting for
pseudogap and bilayer splitting effects for normal (slightly) underdoped Bi2212
(delta=0.15). We show that LDA+DMFT+Sigma_k successfully describes strong
(pseudogap) scattering close to Brillouin zone boundaries. Our calculated
LDA+DMFT+Sigma_k Fermi surfaces and ARPES spectra in presence of the pseudogap
fluctuations are almost insensitive to the bilayer splitting strength. The
LDA-calculated value of bilayer splitting is found to be rather small to
describe experimentally observed peak-dip-hump structure.
