A compound and methods of making thereof having the structure shown below is disclosed. Each Ar is an aromatic group. Each M is palladium, platinum, or rhenium. At least one X in the compound has an aliphatic having at least 1 carbon atom. Each x, each y, and each z is an integer greater than or equal to zero. Each m is an integer greater than or equal to one. n is an integer greater than or equal to three.; 展开▼