Please expert explain me this limiting radius ratio
Dear student
Radius ratio is the ratio of radius of cations to anions, rc/ra of an ionic molecule. It has values between 0.155 to 1.
Below 0.155 the molecule will collapse and the crystal structure cannot exist, this is called the limiting radius ratio.
Limiting radius ratio shows the lowest and highest ratio possible for ions to form a certain type of close packing .
We know that triangular void is smallest in size followed by tetrahedral , octahedral and cubic respectively.
as the size of void increases, it means larger cation can enter the void.
Regards
Radius ratio is the ratio of radius of cations to anions, rc/ra of an ionic molecule. It has values between 0.155 to 1.
Below 0.155 the molecule will collapse and the crystal structure cannot exist, this is called the limiting radius ratio.
Limiting radius ratio shows the lowest and highest ratio possible for ions to form a certain type of close packing .
We know that triangular void is smallest in size followed by tetrahedral , octahedral and cubic respectively.
as the size of void increases, it means larger cation can enter the void.
Regards