The first option for your dome greenhouse coverings is called Sun Selector. It too is 6 mil and is a diffused greenhouse film featuring a 60% light diffusion which reduces shadowing. Also an IR additive, Anti-Drip AD to reduce mold, UVA and dust protection.
Sun Selector I.R. films prevent heat radiation loss from the Greenhouse to the atmosphere, maintain higher foliage temperatures and drier plants, reduce the incidence of frost damage and lead to saving in heating costs.