Vaishali Arunachalam, Kshama Sharma, Kaustubh R. Mote, P.K. Madhu
{"title":"在魔角自旋固体核磁共振中,采用异步五重对称序列实现更好的同核极化转移","authors":"Vaishali Arunachalam, Kshama Sharma, Kaustubh R. Mote, P.K. Madhu","doi":"10.1016/j.ssnmr.2023.101858","DOIUrl":null,"url":null,"abstract":"<div><p>Recoupling, decoupling, and multidimensional correlation experiments in magic-angle-spinning (MAS) solid-state NMR can be designed by exploiting the symmetry of internal spin interactions. One such scheme, namely, <span><math><msubsup><mrow><mi>C</mi><mn>5</mn></mrow><mrow><mn>2</mn></mrow><mrow><mn>1</mn></mrow></msubsup></math></span>, and its supercycled version <span><math><msubsup><mrow><mi>S</mi><mi>P</mi><mi>C</mi><mn>5</mn></mrow><mrow><mn>2</mn></mrow><mrow><mn>1</mn></mrow></msubsup></math></span>, notated as a five-fold symmetry sequence, is widely used for double-quantum dipole-dipole recoupling. Such schemes are generally rotor synchronised by design. We demonstrate an asynchronous implementation of the <span><math><msubsup><mrow><mi>S</mi><mi>P</mi><mi>C</mi><mn>5</mn></mrow><mrow><mn>2</mn></mrow><mrow><mn>1</mn></mrow></msubsup></math></span><span> sequence leading to higher double-quantum homonuclear polarisation transfer<span> efficiency compared to the normal synchronous implementation. Rotor-synchronisation is broken in two different ways: lengthening the duration of one of the pulses, denoted as pulse-width variation (PWV), and mismatching the MAS frequency denoted as MAS variation (MASV). The application of this asynchronous sequence is shown on three different samples, namely, U–</span></span><sup>13</sup>C-alanine and 1,4-<sup>13</sup><span>C-labelled ammonium phthalate which include </span><sup>13</sup>C<sub><em>α</em></sub>-<sup>13</sup>C<sub><em>β</em></sub>, <sup>13</sup>C<sub><em>α</em></sub>-<sup>13</sup>C<sub>o</sub>, and <sup>13</sup>C<sub>o</sub>–<sup>13</sup>C<sub>o</sub> spin systems, and adenosine 5′- triphosphate disodium salt trihydrate (ATP⋅3H<sub>2</sub>O). We show that the asynchronous version performs better for spin pairs with small dipole-dipole couplings and large chemical-shift anisotropies, for example, <sup>13</sup>C<sub>o</sub>–<sup>13</sup>C<sub>o</sub>. Simulations and experiments are shown to corroborate the results.</p></div>","PeriodicalId":21937,"journal":{"name":"Solid state nuclear magnetic resonance","volume":null,"pages":null},"PeriodicalIF":1.8000,"publicationDate":"2023-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Asynchronising five-fold symmetry sequence for better homonuclear polarisation transfer in magic-angle-spinning solid-state NMR\",\"authors\":\"Vaishali Arunachalam, Kshama Sharma, Kaustubh R. Mote, P.K. Madhu\",\"doi\":\"10.1016/j.ssnmr.2023.101858\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<div><p>Recoupling, decoupling, and multidimensional correlation experiments in magic-angle-spinning (MAS) solid-state NMR can be designed by exploiting the symmetry of internal spin interactions. One such scheme, namely, <span><math><msubsup><mrow><mi>C</mi><mn>5</mn></mrow><mrow><mn>2</mn></mrow><mrow><mn>1</mn></mrow></msubsup></math></span>, and its supercycled version <span><math><msubsup><mrow><mi>S</mi><mi>P</mi><mi>C</mi><mn>5</mn></mrow><mrow><mn>2</mn></mrow><mrow><mn>1</mn></mrow></msubsup></math></span>, notated as a five-fold symmetry sequence, is widely used for double-quantum dipole-dipole recoupling. Such schemes are generally rotor synchronised by design. We demonstrate an asynchronous implementation of the <span><math><msubsup><mrow><mi>S</mi><mi>P</mi><mi>C</mi><mn>5</mn></mrow><mrow><mn>2</mn></mrow><mrow><mn>1</mn></mrow></msubsup></math></span><span> sequence leading to higher double-quantum homonuclear polarisation transfer<span> efficiency compared to the normal synchronous implementation. Rotor-synchronisation is broken in two different ways: lengthening the duration of one of the pulses, denoted as pulse-width variation (PWV), and mismatching the MAS frequency denoted as MAS variation (MASV). The application of this asynchronous sequence is shown on three different samples, namely, U–</span></span><sup>13</sup>C-alanine and 1,4-<sup>13</sup><span>C-labelled ammonium phthalate which include </span><sup>13</sup>C<sub><em>α</em></sub>-<sup>13</sup>C<sub><em>β</em></sub>, <sup>13</sup>C<sub><em>α</em></sub>-<sup>13</sup>C<sub>o</sub>, and <sup>13</sup>C<sub>o</sub>–<sup>13</sup>C<sub>o</sub> spin systems, and adenosine 5′- triphosphate disodium salt trihydrate (ATP⋅3H<sub>2</sub>O). We show that the asynchronous version performs better for spin pairs with small dipole-dipole couplings and large chemical-shift anisotropies, for example, <sup>13</sup>C<sub>o</sub>–<sup>13</sup>C<sub>o</sub>. Simulations and experiments are shown to corroborate the results.</p></div>\",\"PeriodicalId\":21937,\"journal\":{\"name\":\"Solid state nuclear magnetic resonance\",\"volume\":null,\"pages\":null},\"PeriodicalIF\":1.8000,\"publicationDate\":\"2023-04-01\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Solid state nuclear magnetic resonance\",\"FirstCategoryId\":\"92\",\"ListUrlMain\":\"https://www.sciencedirect.com/science/article/pii/S0926204023000085\",\"RegionNum\":3,\"RegionCategory\":\"化学\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q4\",\"JCRName\":\"CHEMISTRY, PHYSICAL\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Solid state nuclear magnetic resonance","FirstCategoryId":"92","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S0926204023000085","RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q4","JCRName":"CHEMISTRY, PHYSICAL","Score":null,"Total":0}
Asynchronising five-fold symmetry sequence for better homonuclear polarisation transfer in magic-angle-spinning solid-state NMR
Recoupling, decoupling, and multidimensional correlation experiments in magic-angle-spinning (MAS) solid-state NMR can be designed by exploiting the symmetry of internal spin interactions. One such scheme, namely, , and its supercycled version , notated as a five-fold symmetry sequence, is widely used for double-quantum dipole-dipole recoupling. Such schemes are generally rotor synchronised by design. We demonstrate an asynchronous implementation of the sequence leading to higher double-quantum homonuclear polarisation transfer efficiency compared to the normal synchronous implementation. Rotor-synchronisation is broken in two different ways: lengthening the duration of one of the pulses, denoted as pulse-width variation (PWV), and mismatching the MAS frequency denoted as MAS variation (MASV). The application of this asynchronous sequence is shown on three different samples, namely, U–13C-alanine and 1,4-13C-labelled ammonium phthalate which include 13Cα-13Cβ, 13Cα-13Co, and 13Co–13Co spin systems, and adenosine 5′- triphosphate disodium salt trihydrate (ATP⋅3H2O). We show that the asynchronous version performs better for spin pairs with small dipole-dipole couplings and large chemical-shift anisotropies, for example, 13Co–13Co. Simulations and experiments are shown to corroborate the results.
期刊介绍:
The journal Solid State Nuclear Magnetic Resonance publishes original manuscripts of high scientific quality dealing with all experimental and theoretical aspects of solid state NMR. This includes advances in instrumentation, development of new experimental techniques and methodology, new theoretical insights, new data processing and simulation methods, and original applications of established or novel methods to scientific problems.