"clear separation between" is a perfectly acceptable phrase that can be used in written English.
For example, you could say "The treaty establishes a clear separation between the two countries."
He makes a clear separation between army and pop life.
The song sparrow provides an example of a particularly clear separation between observation and imitation.
In order to overcome these difficulties, there needs to be a clear separation between military and humanitarian aid activity.
CONSOB also wants a clear separation between the two types of audits now required by Italian law.
However, I am bothered by the lack of a clear separation between Muslims and supporters of terrorism.
In him there also appeared the first clear separation between the formal characterization of logical laws and their semantic justification.
There is clear separation between the curves in gas case (to left), and there is no clear separation between the reservoir and deeper section in the Well_1 case.
Thus, for Dewey, there is no clear separation between the aesthetic and the intellectual.
There was no clear separation between the government and the judiciary.
It encourages a clear separation between the probability distribution model and the encoding of information.
After correction, almost all dumbbells show clear separation between the two Si atomic columns.
