As the value of the angular momentum quantum number increases, the number of values of m increases (there are 2 l + 1 values of m) and the complexity of the orbital geometry increases. The d orbitals all possess l = 2. For this value of l, the magnetic quantum number may have values of m = 2, 1, 0, +1, and +2. Only orbitals with m = 0 are real; all other values of m give rise to complex wave functions. As is the case with p orbitals, chemists combine the m = 1 and +1 wave functions (which are complex) to obtain two new functions that are both real. Similarly, the wave functions with m = 2 and +2 are also combined to yield two new real wave functions.
The d orbital with m = 0 is designated z^{2}. The two orbitals created from the m = 1 and +1 orbitals are designated xz and yz. The two orbitals created from the m = 2 and +2 orbitals are designated xy and x^{2}y^{2}. These designations arise from the mathematical formulas for the wave functions and indicate the orientation of the orbital.
Carefully examine the d orbitals for various values of n and the various orientations (d_{z2}, d_{xz}, d_{yz}, d_{xy}, d_{x2y2} ) and answer the following questions.

s Orbitals  p Orbitals  d Orbitals 