H. J. Bernstein's scientific contributions
What is this page?
This page lists the scientific contributions of an author, who either does not have a ResearchGate profile, or has not yet added these contributions to their profile.
It was automatically created by ResearchGate to create a record of this author's body of work. We create such pages to advance our goal of creating and maintaining the most comprehensive scientific repository possible. In doing so, we process publicly available (personal) data relating to the author as a member of the scientific community.
If you're a ResearchGate member, you can follow this page to keep up with this author's work.
If you are this author, and you don't want us to display this page anymore, please let us know.
It was automatically created by ResearchGate to create a record of this author's body of work. We create such pages to advance our goal of creating and maintaining the most comprehensive scientific repository possible. In doing so, we process publicly available (personal) data relating to the author as a member of the scientific community.
If you're a ResearchGate member, you can follow this page to keep up with this author's work.
If you are this author, and you don't want us to display this page anymore, please let us know.
Publications (9)
Interpretation of the fine structure of the NMR spectra of some five-membered "aromatic" heterocyclic ring compounds indicates that spin coupling constants between adjacent protons on the ring and those across the ring are approximately equal. This is in contrast to the situation in six-membered rings where coupling constants between protons ortho...
The proton resonance spectra of pyridine, 2,6-pyridine-d2, 3-pyridine-d1, and 4-pyridine-d1 have been obtained for the pure liquids under conditions of high resolution. The spectra have been analyzed as proton groupings of AB2X2, AB2, perturbed ABX, and B2X2 respectively. The spin-coupling constants obtained from analysis of the simpler spectra of...
The spacing of the doublet in the proton resonance spectrum of this compound was measured over the temperature range of $-70$ to $+90^{\circ} C$. In principle, the coupling constants of the rotational isomers and their energy difference can be evaluated from the observed changes in spacing. Within the limits of the experimental error it was possibl...
The analyses of the ABX, A2X2, and ABXY types of spectra are discussed in detail under the conditions for which the observed spectra give less than the theoretical number of transitions. These conditions for which an observed spectrum is deceptively simple are derived from the general analyses, and experimental examples of such spectra are given.
The proton magnetic resonance spectrum of methyl mercaptan has been analyzed on the basis of the nuclear grouping AB3. The spectrum calculated for agrees very well with that observed.
The proton magnetic resonance spectra of some substituted furans and pyrroles have been analyzed for spin coupling constants and chemical shifts.The relative insensitivity of the spin coupling constants to the nature of the substituent makes it possible to estimate their values in the parent molecules furan and pyrrole. The magnitude of the spin co...
This paper deals with the analysis of the nuclear magnetic resonance spectrum of two pairs of two equivalent nuclei (of spin )whose relative chemical shift is of the same order as the spin-coupling constants of the system (A2B2 in the notation of Part I). The complete matrix is set up and correlated with the results of McConnell, McLean, and Reilly...
This paper is concerned with the general problem of the interpretation and analysis of nuclear magnetic resonance spectra of systems in which chemical shift and spin-coupling constants are of the same order of magnitude. Only nuclei of spin 1/2 are considered. Detailed methods are developed for:(a) Two chemically non-equivalent nuclei of the same s...
Citations
... The overall spectrum can be reproduced using just 48 lines, thus classifying as a 'deceptively simple' spectrum where many transitions are (nearly) degenerate and/or have low transition probabilities [27]. This spectral simplicity made it possible to fit the experimental spectrum and extract a value of 0.43 Hz for the 4 J HH between geminal methyl group in compound 1. ...
... Thiophene (1) was inspected in the early days of NMR leading to definitions of AA'BB' [20] or in a different concept as A 2 B 2 [21] spin systems, which correspond to the [AB] 2 four spin case in Haigh's more potent nomenclature. [22] 2,5-Dihydrothiophene (2) yielded a deceptively simple [A[B] 2 ] 2 type 1 H NMR spectrum at 60 MHz, which was successfully analyzed using weak outer lines. ...
... The 3-H a chemical shift moved from 3.22 ppm to 4.79 ppm because of the ester group at that position. The three additional aromatic protons were centered at 6.51 ppm, 7.15 ppm, and 7.59 ppm, all as doublets of doublets with small coupling constants, in agreement with the findings of Abraham et al. [25] and Bardsley et al. [26]. The 13 C-spectra consisted of five new carbons due to the ester -C=O at 158.71, and four aromatic carbons at 111.68 ppm, 117.32 ppm, 145.23 ppm, and 146.13 ppm. ...
... In 1956-58, several papers appeared by these authors (22,24,27,28,31). Pople provided the quantum-mechanical analysis of a series of progressively more complex spectra produced by the two experimentalists. ...
... We consider the case of molecules containing three CH2 groups, each group having a distinct chemical shift. The geminal protons of each group are chemically equivalent but magnetically inequivalent, thus forming an AA'MM'XX' spin system in Pople's notation [17]. The dominant intra-pair dipole-dipole couplings DAA', DMM', and DXX' do not affect relaxation of LLSs for reasons of symmetry, while out-of-pair dipole-dipole couplings such as DAM, DAM', etc. have much smaller contributions to their relaxation rates because of the larger internuclear distances. ...
... Two of the eigenstates of the Hamiltonian H are simply the triplet states |T ±1 , whereas the other two eigenstates are linear combinations of |S 0 and |T 0 [35,43]. Thus, the states {|S 0 , |T 0 } form an effective two-level subspace which can be conveniently represented by the Bloch sphere as shown in Fig. 2. The coupling term −πΩ can be used to interchange populations between |T 0 and |S 0 states. ...
