# References indicate sr is fcc at standard state

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References indicate Sr is FCC at standard state.
Example What maximum diameter may a spherical impurity have if it is centered on the cube edge of a strontium crystal at standard state (0 o C, 1 atm), without introducing distortion? References indicate Sr is FCC at standard state.
Example What maximum diameter may a spherical impurity have if it is centered on the cube edge of a strontium crystal at standard state (0 o C, 1 atm), without introducing distortion? References indicate Sr is FCC at standard state. It fits on the cube edge center perfectly. Under this condition the lattice parameter for FCC can be written as:
Example What maximum diameter may a spherical impurity have if it is centered on the cube edge of a strontium crystal at standard state (0 o C, 1 atm), without introducing distortion? References indicate Sr is FCC at standard state. It fits on the cube edge center perfectly. Under this condition the lattice parameter for FCC can be written as: Therefore: a = 2 R + 2 r 2 r = a 2 R
Example What maximum diameter may a spherical impurity have if it is centered on the cube edge of a strontium crystal at standard state (0 o C, 1 atm), without introducing distortion? References indicate Sr is FCC at standard state. It fits on the cube edge center perfectly. Under this condition the lattice parameter for FCC can be written as: Therefore: But a and R are related … for FCC: a 2 = 4 R a = 4 R 2 a = 2 R + 2 r 2 r = a 2 R
Example What maximum diameter may a spherical impurity have if it is centered on the cube edge of a strontium crystal at standard state (0 o C, 1 atm), without introducing distortion? References indicate Sr is FCC at standard state. It fits on the cube edge center perfectly. Under this condition the lattice parameter for FCC can be written as: Therefore: But a and R are related … for FCC: Therefore: d = 2 r = 4 R 2 R 2 a 2 = 4 R a = 4 R 2 a = 2 R + 2 r 2 r = a 2 R
Example What maximum diameter may a spherical impurity have if it is centered on the cube edge of a strontium crystal at standard state (0 o C, 1 atm), without introducing distortion? References indicate Sr is FCC at standard state. It fits on the cube edge center perfectly. Under this condition the lattice parameter for FCC can be written as: Therefore: But a and R are related … for FCC: Therefore: a 2 = 4 R a = 4 R 2 a = 2 R + 2 r 2 r = a 2 R 100 pm = 1Å d = 2 r = 4 R 2 R 2
Example What maximum diameter may a spherical impurity have if it is centered on the cube edge of a strontium crystal at standard state (0 o C, 1 atm), without introducing distortion? References indicate Sr is FCC at standard state. It fits on the cube edge center perfectly. Under this condition the lattice parameter for FCC can be written as: Therefore: But a and R are related … for FCC: Therefore: a 2 = 4 R a = 4 R 2 a = 2 R + 2 r 2 r = a 2 R d = 2 r = 4 R 2 R 2 d = 2 r = 4(2.15 Å) 2(2.15 Å) = 1.78 Å 2
a a a <100> a 2 <110> a <100> a <100> <100> <100> a <100> a <100> a 2 <110> a 2 <110> a 3 <111> Three important components to cubic crystallography: (1) Cube geometry
x y z a a a [1 1 0] x y z a a a [1 0 0] (1 0 0) x y z a a a For cubic unit cells: Plane ( h k l ) is perpendicular to direction [