Question:

Apart from the acoustic modes, 9 optical modes are identified from the measurements of phonon dispersions of a solid with the chemical formula $A_nB_m$ , where $A$ and $B$ denote the atomic species, and $n$ and $m$ are integers. Which of the following combinations of $n$ and $m$ is/are possible?

GATE PH - 2024
GATE PH

Updated On: Jul 12, 2024

$n = 1, m = 1$
$n = 2, m = 2$
$n = 3, m = 1$
$n = 4, m = 4$

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The Correct Option is B, C

Solution and Explanation

The correct Answers are (B): ,(C):

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The Correct Option is B, C

Solution and Explanation

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