My husband retired (early) from LG in 2003, and died last year. The pension providers were very helpful, telling me exactly what I would get and when I would get it. I received his full pension for 3 months after his death, and then it dropped back to half (it actually worked out as more than half, net, because I pay less tax).
I also found that my State pension was increased as a result of his contributions, something I hadn't expected. I didn't have to claim this, they just paid it. He earned - and contributed - a lot more than I ever did, which may be why this happened.