[1s]-s a [2p]-p- [4o]-o i [1u]-u i o-t-[2y]-i- [4u] - y [1t]-- s-s a [2p]-p- [4o]-o i [1u]-u i o-t-[2y]-i- [4u] - y [1t]-- [1s] d s p [5a]-o- [1s] d s p [5a]-o- [6s]-s a [2p]-d- [5a] - p [4o]-- [1s]-s a [2p]-p- [4o]-o i [1u]-u i o-t-[2y]-i- [1u]--[4o]-- [1s]