Quasilocalization of extra electrons in high density methane and ethane gases

The extent of electron quasilocalization in the high density gases is greater in ethane than in methane. However, the density required for quasilocalization in methane is n/n_c > 0.1, while that in ethane is n/n_c > 0.4, where n_c is the critical density. The mobilities in methane and ethane cross at n = 6 × 10²¹ molecules/cm³, in the respective fluids along their vapor/liquid coexistence curves.