This allows calculating approximate wavefunctions such as molecular orbitals. Valence bond theory views bonds as weakly coupled orbitals (small overlap). See Linear combination of atomic orbitals molecular orbital method. Electrons in s orbitals are held more tightly than electrons in p orbitals. An incoming electron will experience significant repulsion from the electrons in these orbitals. The 2p elements exhibit near ideal hybridisation with orthogonal hybrid orbitals. The other two 2p orbitals remain unhybridized. The image to the right shows the first few hydrogen atom orbitals (energy eigenfunctions). The sigma orbital formed by the "p" orbitals aligned along the molecular axis is unfilled. Covalent character is achieved by using the s and possibly p orbitals. Lanthanide ions have notable luminescent properties due to their unique 4f orbitals. In a field of about 10 teslas atomic orbitals deform into rod shapes. This increased stability is due to the unique properties of aromatic molecular orbitals. The hypervalent component consists of resonant bonds using p orbitals. Thus, five spatial orbitals in total.