//chapter9,Example9_9,pg 240

lam=0.58*10^-10

theta1=6.5*(%pi/180)

theta2=9.15*(%pi/180)

theta3=13*(%pi/180)

//from bragg's law

d1=lam/(2*sin(theta1))*10^10

d2=lam/(2*sin(theta2))*10^10

d3=lam/(2*sin(theta3))*10^10

printf("interplannar spacing of crystal\n")

printf("%.2f:",d1);printf("%.2f:",d2);printf("%.2f",d3);