Pdf the theory of nuclear quadrupole resonance spectroscopy is summarized. Feasibility of nuclear quadrupole resonance as a technique for detecting personborne explosives michael l. Nuclear quadrupole resonance for explosive detection. Among these is nitrogen14 14n and nitrogen is a constituent of explosives used in landmines, such as rdx and tnt. How weak rf pulses and double resonance crossrelaxation contribute to explosives detection. Instead, nqr exploits the fact that some nuclei possess an electric quadrupole moment, which can be thought of as arising from two backtoback electric dipoles positive and. Nuclear quadrupole resonance nqr the resonance absorption of electromagnetic energy in a crystal owing to transitions between energy levels that are formed as a result of the interaction of nuclei that have an electric quadrupole moment with the crystal electric field.
Pdf role of spin state on the geometry and nuclear. A coil antenna being used to detect the signal from the sample right 3. This table is a compilation of experimental measurements of static magnetic dipole and electric quadrupole moments of ground states and excited states of atomic nuclei throughout the periodic table. A selective absorption phenomenon observable in a wide variety of polycrystalline compounds containing nonspherical atomic nuclei when placed in a magnetic radiofrequency field. The nuclei that show nqr spectra are listed and the. Bryce solidstate nuclear magnetic resonance and nuclear quadrupole resonance as complementary tools to study quadrupolar nuclei in solids, concepts magn. Table of nuclear magnetic dipole and electric quadrupole. Research laboratory nrl has expertise in solid state nuclear mag netic resonance nmr. They performed a detailed perturbationnqr regime, where little or. This moment is a measure of how the nuclear charge distribution deviates away from spherical symmetry and it happens in nuclei with greater spin or equal to.
Nuclear quadrupole resonance in amorphous semiconductors in. Explosives detection with nuclear quadrupole resonance. Pdf nuclear quadrupole resonance, applications researchgate. Paul alan, a nuclear quadrupole resonance study of heavy transition metal halide compounds with bridging halogen atoms 1972. Electric field gradient nuclear quadrupole resonance double resonance nitrogen mustard asymmetry factor these keywords were added by machine and not by the authors. Nuclear quadrupole resonances in compact vapor cells. Nuclear quadrupole resonance nqr is the study of the energy splittings due to interaction of the elec tric quadrupole moment of the nucleus with the elec. Nuclear quadrupole resonance spectroscopy springerlink. A nuclear quadrupole resonance study of heavy transition.
View nuclear quadrupole resonance research papers on academia. Encyclopedia of spectroscopy and spectrometry, edition. Journal of molecular structure, 83 1982 1 7 1 elsevier scientific publishing company, amsterdam printed in the netherlands nuclear quadrupole resonance spectra database h. Chihara department of chemistry, faculty of science, osaka university, toyonaka 560 and japan association for international chemical information jaici, 216 yayoi, bunkyoku, tokyo 1, japan abstract a computer. Recent developments in solidstate nuclear magnetic resonance. Nuclear quadrupole resonance for explosive detection hideo itozaki and go ota graduate school of engineering science, osaka university machikaneyama toyonaka, osaka, 5608531, japan abstract abstract a nuclear quadrupole resonance detector has been developed. Nuclear magnetic resonance nmr has been widely used in the context of quantum information processing qip. Nuclear quadrupole resonance nqr is a radio frequency rf spectroscopy technique for solid materials the instrumentation is like nmr but nqr doesnt require an applied b 0 field because the physical mechanism is different there are benefits and drawbacks to nqr as compared with nmr. Nuclear magnetic resonance nmr spectroscopy direct observation of the hs and cs of a molecules nuclei are positively charged and spin on an axis. Temperature effects in nuclear quadrupole resonance. A read is counted each time someone views a publication summary such as the title, abstract, and list of authors, clicks on a figure, or views or downloads the fulltext. Nuclear quadrupole resonance nqr is the study of the energy splittings due to interaction of the electric quadrupole moment of the nucleus with the electric field gradient that exists at the nuclear site. Nuclear spectroscopy is a superordinate concept of methods that uses properties of a nucleus to probe material properties.
The resonance effect comes from the fact that valence electrons preferentially align with some of the 14 n. Nuclear quadrupole resonance nqr article about nuclear. Feasibility of nuclear quadrupole resonance as a technique. Locked nuclear quadrupole resonance spectrometer for pressure. Temperature effects in nuclear quadrupole resonance spectroscopy. Pdf the applications of nuclear quadrupole resonance nqr are surveyed. These include studies of molecular structure in the solid state. Nuclear magnetic resonance, first demonstrated in 1946, takes advantage of the fact that certain atomic nuclei possess magnetic dipole moments.
Nuclei with a spin greater than 12, such as 14 n, have a nuclear electric quadrupole moment that interacts with the electric field of the surrounding electrons, producing an electric quadrupole coupling. Ab initiocalculations of nuclear quadrupole resonance frequencies. Nuclear quadrupole resonance has much in common with nuclear magnetic resonance nmr, the fundamental physical process that makes magnetic resonance imaging possible. Calculation of the nuclear quadrupole resonance spectra of. High sensitivity nuclear quadrupole resonance of light nuclei. Locked nuclear quadrupole resonance spectrometer for pressure measurements ronald c. Stone, oxford physics, clarendon laboratory parks road, oxford ox1 3pu u. Nuclear quadrupole resonance spectra database sciencedirect. In nmr the splitting of the energy levels, and therefore the frequency observed, occurs because of the interaction of the nuclear magnetic moment with an external magnetic field. Nuclear quadrupole resonance nqr and nuclear magnetic resonance nmr studies on sup 63,65cu have demonstrated the the resonance properties of these nuclei can give important information about the electronic structure of the high temperature superconductor ybasub 2cusub 3osub 7minusx as well as the exchange coupling energy between the cu2 sites. Role of spin state on the geometry and nuclear quadrupole resonance parameters in hemin complex.
A modification of nuclear quadrupole double resonance with coupled multiplet is proposed which can be used for the measurement of the dipolar structure of the 17o nuclear quadrupole resonance. Nuclear m agnetic resonance sp ectroscopy nuc lear quadrupole resonance applications theory offered townes and dailey. Many nuclei with spins greater than vz have a quadrupole moment and most of these quadrupole moments have been measured and tabulated. Nuclear quadrupole resonance nqr uses radiofrequency rf magnetic fields to induce and detect transitions between sublevels of a nuclear ground state, a description that also applies to nuclear magnetic resonance nmr. However, despite the great similarities between nmr and nuclear quadrupole resonance nqr, no experimental implementation for qip using nqr has been reported. The sensitivity of the slusher and hahns nuclear quadrupole double resonance technique is calculated in general for an arbitrary nuclear spin s of the quadrupole nuclei and for an arbitrary asymmetry parameter eta of the electric field gradient tensor. Table of nuclear magnetic dipole and electric quadrupole moments n. Some examples of nuclear quadrupole moments nucleus i q 1028m2 2h 1 2. Journal of research of the national bureau of standards. The quadrupole moment, nonzero only for nuclei with spin quantum number i greater than or equal to 1, is a nuclear. Table of nuclear magnetic dipole and electric quadrupole moments. In the simplest case, for example, 35cl in solid cl 2, nqr is associated with the precession of the angular. This process is experimental and the keywords may be updated as the learning algorithm improves. Here viiand ye are the resonance frequencies when the electronic magnetic moment is in a direction parallel and perpendicular to the caxis respectively, 0 the angle between the magnetic moment and the caxis, q the principal value of the e.
Nuclear pure quadrupole resonance nqr is a resonance technique that provides distinctly different information from that provided by nuclear magnetic resonance nmr. Nuclear quadrupole resonance nqr, a derivative of nuclear magnetic resonance nmr, is a bulk inspection technology which can be used to detect certain chemical elements which have an electric quadrupole moment. Nmr references for quadrupole hamiltonian pascalman. If the inline pdf is not rendering correctly, you can download the pdf file here.
Nuclear quadrupole resonance as a nondestructive testing tool. The three energy levels of 14n and corresponding transition frequencies left 2. Nuclear quadrupole resonance nqr spectroscopy wulfsberg. Vanderhart institute for materials research, national bureau of standards, washington, d. Nuclear quadrupole resonance how is nuclear quadrupole. Nuclear magnetic resonance nmr and nqr phenomena are caused by applying radiofrequency wave having. Nuclear quadrupole resonance article about nuclear. By emission or absorption of radiation from the nucleus information of the local structure is obtained, as an interaction of an atom with its closest neighbours. Abstract the article concerns the usefulness of nuclear quadrupole resonance nqr spectroscopy in inorganic and organometallic chemistry. Unlike nmr, nqr transitions of nuclei can be detected in the absence of a magnetic field, and for this reason nqr spectroscopy is referred to as zero field nmr. The gradient of an electrical field in a place of a presence. Ab initio calculations of nuclear quadrupole resonance. Pdf nuclear quadrupole resonance, theory researchgate.
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