No expert but I believe so. At least in some cases. The justification being along the lines of they not putting money away for their own pension as in those years they were relying on their husband's.
When my mum and ex step father separated, she never asked for a share of his pension; instead she got a bigger share of the proceeds from selling the house.
However, the ex wife of my mum's new husband (my current step father) has a claim on his pension as part of their divorce settlement, so his pension is reduced, as her share is automatically paid out before it goes into his bank.
If she is going to do it, she really need to get a share of the pot upfront as if the husband has a subsequent divorce or divorces, then she may not get all she is entitled to by the agreement. Of course this also applies if its the wife who has the pension pot and the husband who is receiving the settlement.