User talk:B.esselman


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Greetings, I have noticed a number of your contributions to articles. You are raising some very interesting points, but I am afraid you are not following wikipedia guidelines. Much of what you say is original research and it is not supported by sources. It is also dogmatic, where there are grounds for reasonable disagreement. Let me take two examples. First, your very recent edits to Orbital hybridisation under the heading "Correct Explanation", where you argue that there are not two equivalent lone pairs in water. This is entirely a matter of how you define things. MO or DFT will give orbitals that reflect the symmetry of the molecule, so, yes, you get one lone pair in the plane and a p orbital perpendicular to the plane. However, if you transform the MOs to localised orbitals (a unitary transformation that leaves the wave function unaltered), you get two equivalent bond orbitals and two equivalent lone pairs (each being the MO lone pair ± the p orbital). It is far too strong, to say that the lone pairs are not equivalent. Second, VSEPR has no connection to hybrids or Lewis structures. Read what Gillespie says. This is a common misconception. It is also incorrect to think that VSEPR ideas can entirely account for the correct bond angle. In ab initio calculations on water, it is clear that you get a very poor bond angle (far too small) unless you add d orbitals to the basis set. You need polarization to open up the angle to the correct value. Second, in your edits to VSEPR theory, you are wrong to say "VSEPR fails to predict the correct hybridization of the oxygen in water molecules". VSEPR does not predict hybridization. It predicts shape. It has no link to hybridization. I am afraid that your edits require a serious clean up. Finally I suggest that participate in the WikiProject Chemistry and discuss some of your ideas there. Again, welcome to WP. -- Bduke   (Discussion)  22:50, 24 April 2011 (UTC)