The present application relates to method for oligomerizing olefin or for producing polyalphaolefin utilizing catalyst mixtures comprising aluminum halides and an organic liquid carrier. A process comprising contacting 1) a catalyst mixture comprising i) an aluminum trihalide and ii) an organic liquid carrier comprising first olefins, wherein the organic liquid carrier first olefins comprise at least 60 mole % 1,2-disubstituted olefins, trisubstituted olefins, or any combination thereof; and 2) a monomer comprising second olefins to form an oligomer product. An oligomer product produced by the process comprising contacting 1) a catalyst mixture comprising i) an aluminum trihalide and ii) an organic liquid carrier comprising first olefins, wherein the organic liquid carrier olefins comprise at least 75 mole % 1,2-disubstituted olefins, trisubstituted olefins, or any combination thereof; and 2) a monomer comprising second olefins to form an oligomer product.