How do you calculate the moment of inertia of a polyatomic molecule

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How do you calculate the moment of inertia of a polyatomic molecule around an arbitrary axis of rotation? (A) where rj is the distance of atom j to the COM where rj is the distance of atom j to the COM (C) where rj is the distance of atom j to the rotation axis (D) where rj is the distance of atom j to the rotation axis (E) where rj is the distance of atom j to the COM

How do you calculate the moment of inertia of a polyatomic molecule around an arbitrary axis of rotation? (A) where rj is the distance of atom j to the COM where rj is the distance of atom j to the COM (C) where rj is the distance of atom j to the rotation axis (D) where rj is the distance of atom j to the rotation axis (E) where rj is the distance of atom j to the COM The definition of m is problematic here, also rj is not the distance to the COM rj is not the distance to the COM Baloney Baloney

Based on the selection rule for a purely rotational transition, DJ=±1, what does does a rotational spectrum of a rigid rotator look like? (A) A series of equally spaced peaks. (B) A series of peaks with decreasing difference in frequency. (C) Just one peak, because DJ is always ±1. (D) A series of peaks with increasing difference in frequency. n n n

Based on the selection rule for a purely rotational transition, DJ=±1, what does does a rotational spectrum of a rigid rotator look like? (A) A series of equally spaced peaks. (B) A series of peaks with decreasing difference in frequency. (C) Just one peak, because DJ is always ±1. (D) A series of peaks with increasing difference in frequency. n n n

Is the probability distribution of a rigid rotator in an eigenstate physically rotating? (A) Yes. (B) No.

Is the probability distribution of a rigid rotator in an eigenstate physically rotating? (A) Yes. (B) No.

Based on the selection rules for purely rotational electric dipole transitions, does HD have a microwave spectrum? (A) Yes. (B) No.

Based on the selection rules for purely rotational electric dipole transitions, does HD have a microwave spectrum? (A) Yes. Although one might suspect otherwise, HD does have a small electric dipole moment (ca. 8.85·10-4 D). It comes from the adiabatic correction to the BOA and can be explained by the difference in the reduced mass of and electron in the vicinity of the proton vs. the deuteron. (B) No.