What is the structure of noble gas atoms?

Noble gases are a group of chemical elements that make up group 18 on the periodic table. These gases have similar properties under standard conditions: they are all odorless, colorless, monoatomic gases with very low chemical reactivity. The six noble gases that occur naturally are helium (He), Neon (Ne), Argon (Ar), Krypton (Kr), Xenon (Xe), and Radon (Rn). The outer shell of valence electrons is considered “complete” in noble gases, which gives them little propensity to participate in chemical reactions.