The Cambridge Grammar of the English Language by Huddleston and Pullum (CGEL) says on page 801 regarding Position of negator in clauses with subject–auxiliary inversion:
1. Generally:
Clauses with subject–auxiliary inversion normally have the subject immediately following the auxiliary verb. The negative marker will thus precede the subject in synthetic [don't, aren't, etc.] negation but follow the subject in analytic [do not, are not, etc.] negation:
- UNGRAMMATICALDoes not she agree with me?
- OKDoesn't she agree with me?
- OKDoes she not agree with me?
In [2] we have synthetic negation and the negative marker precedes the subject (she). [3] is an example of analytic negation where not follows the subject – [1] breaks this rule, and is consequently ungrammatical as CGEL explains (boldface mine):
In general the word not cannot come between the auxiliary and the subject, as shown in [1].
2. But...
The construction with not preceding the subject is not completely excluded, however: it is occasionally found as an alternant of the normal pattern where not follows the subject. Compare:
- Do most self-indulgent public officials not accept bribes?
- Do not most self-indulgent public officials accept bribes?
Construction [5] is a survival of an older pattern‡ where not was quite generally permitted in this position. In speech it would be highly unnatural except in extremely formal declamation. But in writing it will still be found in sources not permitting synthetically negated auxiliaries. It is normally restricted to cases where the subject is relatively long, where it serves to avoid the lengthy interruption between auxiliary verb and not which makes [4] too sound somewhat stilted.1
1We have noted, however, that synthetic negatives are not permitted in inverted conditionals, and this may facilitate the use of the construction with not preceding the subject: She might have regretted her smallness had not all the parts been so well-proportioned.
‡ Here's a chart clearly showing how that "older pattern" has effectively vanished since its heyday a couple of centuries ago...
