ABC26IN0168 · Inorganic Spectroscopy
Subject: Inorganic Chemistry · Chapter: Inorganic Spectroscopy · Topic: Inorganic Spectroscopy – General · Exam: CSIR-NET DEC 2019 · Marks: 2 · Difficulty: Hard
For the complex shown below in non-fluxional state, the expected ${}^{31}\mathrm{P}\{{}^{1}\mathrm{H}\}$ NMR resonance(s) is/are $[{}^{31}\mathrm{P}=\mathrm{I}=1/2]$ 
(a)one singlet
(b)one doublet
(c)two Singlets
(d)two doublets
Answer
SELF-PRACTICE — the source book printed no answer.
Nothing is invented here, so this question has no answer on record.
Explanation
Both phosphorus are chemically different; $^{2}J_{P-P}$ and $^{3}J_{P-P}$ are possible. Signal for $P = (2NI^{*}+1) = [2\times1\times\tfrac12+1] = 2 \rightarrow$ doublet. Signal for $P^{*} = (2NI+1) = (2\times1\times\tfrac12+1) = 2 \rightarrow$ doublet.