NMR measurement of the nuclear shielding isotope shift in molecular hydrogen

Isotope Effects on Nuclear Magnetic Shielding in Molecular Hydrogen

“…The measured secondary isotope effect in the hydrogen deuteride molecule 1 ΔD­( 2/1 H) = σ HD D – σ DD D = −47.3(3) ppb is in agreement with the value reported in ref , −49(4) ppb, and results reported by Beckett, −46.9(5) ppb at T = 296 K. Moreover, the result of calculations based on spin-rotation constants, −45(7) ppb, is within the experimental uncertainty of this result. It is also close to other values available in the literature, which were not extrapolated to the zero-density limit.…”

“… a 1 Δ X ( 3/1 H) = 1 Δ X ( 3/2 H) + 1 Δ X ( 2/1 H) for X ∈ {H, D, T}. Literature data of uncertainty greater than 10 ppb is not shown. b Ref . c Ref . d Ref . e Ref . f Ref . g Ref . …”

A Crystallizable f‐Element Tuck‐In Complex: The Tuck‐in Tuck‐over Uranium Metallocene [(C5Me5)U{μ‐η5:η1:η1‐C5Me3(CH2)2}(μ‐H)2U(C5Me5)2]

“…Complex 7 reacts with (Et 3 NH)BPh 4 to form the cation [(C 5 Me 5 ) 2 U]BPh 4 [25] cleanly with evolution of hydrogen as monitored by 1 (Figure 2). Reaction of 7 with C 6 H 5 OD gave HD [28] and a product that had 2 D NMR resonances at 3.1 ppm consistent with the presence of deuterium in place of hydrogen in C 5 Me 5 À rings of 8.…”

Temperature dependence of the carbon-13 proton spin-spin coupling constant in gaseous methane

“…Beckett and Carr [8] carried out a very accurate N.M.R. study of HD gas and observed the coupling constant to increase from 42.94 (_+0-04)Hz at 40 K to 43.13 (__+ 0.015)Hz at 294 K. From their results it was possible to show [9] that the value of the coupling constant at equilibrium geometry is 40.62 ( + 0-06)Hz, considerably different from that observed in the gas at any temperature, and to obtain a value for the bond length dependence of the shielding.…”