What are the partial charges of on the atoms in a SN2 reaction?

The nucleophile is normally negatively charged and has a lone pair of electrons. This would make you think the transition state would have a negative charge on the nucleophile. The leaving group also is taking the electrons from the molecule with it. So what is the charge separation?

Here are conflicting images.

First image

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Second image

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    $\begingroup$ Not quite sure what you mean by So what is the charge separation? For SN2 reaction of bromide with chloroethane, bromide has -1 charge as reaction "starts" and chloride has -1 charge when the reaction "ends." $\endgroup$ – MaxW Jul 30 '18 at 1:15
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    $\begingroup$ ? I don't see any "conflict" between the links. What do you think is different/wrong? $\endgroup$ – MaxW Jul 30 '18 at 14:15
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    $\begingroup$ That just isn't correct. For which of the images do you think that there is a positive charge on the nucleophile?!? For the second the leaving atom isn't even shown... $\endgroup$ – MaxW Jul 30 '18 at 17:17
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    $\begingroup$ Take a closer look at the second image. There are partial negative charges on the nucleophile and the leaving group, and a partial positive charge on the carbon center. Your images are in accordance with one another. $\endgroup$ – ringo Jul 30 '18 at 17:26
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    $\begingroup$ I think this illustrates nicely why looking at multiple sources is good. Two different representations get you thinking about what is really going on... $\endgroup$ – MaxW Jul 30 '18 at 18:35

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