Between each pair of minimum energy structures, there is a conformation corresponding to a local maximum in the energy function. You can examine the region around one of the local maxima by repeatedly setting phi to values near that peak, minimizing, and seeing what happens. Repeat the search for the local maximum two or three times. Whatever the outcome of your repeated efforts, be prepared to discuss the issue of repeatability . The conformational energy surfaces for the chlorine and water molecules that you built each have only one minimum.
Butane has more than one, and the number of energy minima goes up rapidly with molecular size.
For large molecules, this generally leads to a difficulty commonly referred to as the multiple minimum problem .