UPDATE 6-BlackRock lands BGI funds, Barclays boosts capital

* BlackRock to buy BGI for $13.5 bln in cash, shares

* Deal makes BlackRock world's biggest asset manager

* Barclays sees Tier 1 capital ratio up 150 bps to 8 pct

* Diamond set for $36 million from BGI stake

* BlackRock shares down 3.3 pct, Barclays fall 4.1 pct (Updates share price, adds when deal is expected to close, advisers, and potential dividend changes)

By Svea Herbst-Bayliss and Steve Slater

BOSTON/LONDON, June 12 (Reuters) - BlackRock Inc (BLK.N: Cotización), the fund manager that has been one of the biggest winners of the credit crunch, has snapped up Barclays Global Investors for $13.5 billion in a deal creating the world's largest money manager.

The combined company, to be called BlackRock Global Investors, will have roughly $2.8 trillion of assets under management, more than double BlackRock's current size. [ID:nN11525846].

Barclays (BARC.L: Cotización), Britain's second-biggest bank, will gain much-needed capital from the cash-and-stock deal.