( The ( ( are ( called ( ( one-electron orbitals ) ( -LRB- ( ( often ( called ( hydrogen-like ( atomic orbitals ) ) ) ) -RRB- ) ) ) ) ) . ) )
(ROOT (S (NP (NNP The)) (VP (VBP are) (VP (VBN called) (NP (NP (JJ one-electron) (NNS orbitals)) (PRN (-LRB- -LRB-) (VP (ADVP (RB often)) (VBN called) (NP (JJ hydrogen-like) (JJ atomic) (NNS orbitals))) (-RRB- -RRB-))))) (. .)))
The are called one-electron orbitals (often called hydrogen-like atomic orbitals).
(ROOT (S (NP (EX There)) (VP (VBP are) (NP (NP (CD one) (NNS electrons)) (PP (IN in) (NP (DT the) (NN hydrogen) (NN atom))))) (. .)))