Unit aS
Name attosiemens
Category Electrical Conductance
Details An attosiemens (aS) is a unit of electrical conductance in the International System of Units (SI). It is a derived unit that quantifies the ease with which an electrical current can pass through a material or a component. The larger the conductance, the easier the flow of electric current through the material.

The siemens is the SI unit for electrical conductance and was formerly called mho (the reciprocal of ohm, which is the unit of electrical resistance). However, when dealing with very small conductance values, the attosiemens (aS) unit is used to represent these minuscule values more clearly.

The prefix "atto" means 10^(-18) in the SI system, so 1 attosiemens (aS) is equal to 10^(-18) siemens (S). In other words, 1 aS is a conductance of one billionth of a billionth of a siemens. This unit is commonly used in scenarios where extremely low conductance values need to be measured or described, such as in biochemical reactions or microscopic structures.