Can Bravais Lattices Be Expressed as a Combination of Primitive Vectors?

AI Thread Summary
The discussion focuses on expressing vectors of the body-centered cubic (bcc) Bravais lattice using two different sets of primitive vectors, a1, a2, a3 and b1, b2, b3. The user seeks guidance on demonstrating that any vector R formed by the first set can also be represented by the second set of vectors. A participant suggests that the solution involves expressing each vector a as a combination of the b vectors and hints at the sum of b1, b2, and b3. The conversation also touches on the concept of reciprocal lattices, although one participant admits confusion regarding this concept. Overall, the thread emphasizes the mathematical relationship between different primitive vector representations in crystallography.
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I have three primitive vectors a1,a2,a3 for the body-centered cubic (bcc) Bravais can be chosen as

a1=ax
a2=ay
a3=(a/2)(x+y+z)

or, for instance, as

b1=(a/2)(y+z-x)
b2=(a/2)(z+x-y)
b3=(a/2)(x+y-z)

where x,y,z are unit vectors.

Now I should show that any vector of the form

R=n1a1+n2a2+n3a3
where n1,n2,n3 are integers

can be presented as

R=m1b1+m2b2+m3b3
where m1,m2,m3 are integers

Do anyone have an idea how I can do this?
Does it help me if I construct reciprocal lattice?

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Hi Mythbusters!

dunno wot a reciprockle lattice is :confused:

but all you need to do is to express each a as a combination of bs :smile:

Hint: to get you started, what is b1 + b2 + b3 ? :wink:
 
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