A magnetometer includes a vapor cell having at least one wall, a chamber defined by the at least one wall, and alkali metal atoms disposed in the chamber to produce an alkali metal vapor in the chamber, wherein the at least one wall includes an oxide-containing interior surface; and an anti-relaxation coating disposed on the oxide-containing interior surface of the at least one wall of the vapor cell, wherein the anti-relaxation coating is a reaction product of the oxide-containing interior surface of the at least one wall with at least one mono- or dichlorosilane compound.