 The next six elements on the periodic table are expected to be the last main-group elements in their period, and are likely to be similar to the 5p elements indium through xenon.In elements 167 to 172, the 9p1/2 and 8p3/2 shells will be filled.Their energy eigenvalues are so close together that they behave as one combined p-subshell, similar to the non-relativistic 2p and 3p subshells.