... DOI: 10.1039/C2DT32008H (Paper) Dalton Trans., 2013, 42, 1461-1475. ... 2072 cm −1 . 28 Given the similar cone angles of Cy 3 P and i Pr 3 P, it is not clear why [(Cy 3 P) 2 Ni] 2 (μ-N 2 ) provides (Cy 3 P) 2 Ni(η 1 -N 2 ) in solution whereas there is no sign that 5 converts to ...