Nickel(II) complex of a biradical: Structure, magnetic properties, high NMR temperature sensitivity and moderately fast molecular dynamics
| Parent link: | Sensors and Actuators B: Chemical Vol. 239.— 2017.— [P. 405–412] |
|---|---|
| Corporate Author: | |
| Other Authors: | , , , |
| Summary: | Title screen A novel nickel(II) complex of a tridentate iminonitroxyl biradical, [Ni(bisimpy)MeOH(ReO4)2], (1) (bisimpy = 2,6-bis(4,4,5,5-tetramethyl-4,5-dihydro-1H-imidazol-2-yl-1-oxyl)pyridine) was structurally and magnetically characterized. Due to an effective separation of the molecules in solid the magnetic behavior of 1 differs considerably from that of a related complex studied earlier, the spin carriers in the former having been strongly ferromagnetically coupled even at room temperature. Dynamic behavior of the paramagnetic cation [Ni(bisimpy)(CD3OD)3] in CD3OD solution was studied by 1H NMR. A temperature dependence of the spectrum of 1 has been analyzed using a dynamic NMR approach. It was shown that an interconversion of two conformers is liable for a fast dynamic process occurring in solution of 1 at elevated temperatures. An estimated value of ?G‡(298 K) for this process was found to be of 59 ± 3 kJ/mol. It was confirmed that a considerable extension of the measurable rate constants range compared to that for diamagnetic compounds is a result of the paramagnetic chemical shifts in the Ni complex. Application of paramagnetic d-metal complexes as probes for studying of the free-energy changes in chemical exchange processes, as well as the advantages of this method compared to diamagnetic species are considered. The investigated complex represents an example of the new type of thermometric NMR sensors being to our knowledge is the most temperature sensitive reagent among the d-metal paramagnetic coordination compounds. Режим доступа: по договору с организацией-держателем ресурса |
| Language: | English |
| Published: |
2017
|
| Subjects: | |
| Online Access: | https://doi.org/10.1016/j.snb.2016.08.015 |
| Format: | Electronic Book Chapter |
| KOHA link: | https://koha.lib.tpu.ru/cgi-bin/koha/opac-detail.pl?biblionumber=655965 |
MARC
| LEADER | 00000naa0a2200000 4500 | ||
|---|---|---|---|
| 001 | 655965 | ||
| 005 | 20250401141206.0 | ||
| 035 | |a (RuTPU)RU\TPU\network\22305 | ||
| 090 | |a 655965 | ||
| 100 | |a 20171016d2017 k||y0rusy50 ba | ||
| 101 | 1 | |a eng | |
| 102 | |a NL | ||
| 135 | |a arcn ---uucaa | ||
| 181 | 0 | |a i | |
| 182 | 0 | |a b | |
| 200 | 1 | |a Nickel(II) complex of a biradical: Structure, magnetic properties, high NMR temperature sensitivity and moderately fast molecular dynamics |f S. P. Babailov [et al.] | |
| 203 | |a Text |c electronic | ||
| 300 | |a Title screen | ||
| 320 | |a [References: p. 411-412 (73 tit.)] | ||
| 330 | |a A novel nickel(II) complex of a tridentate iminonitroxyl biradical, [Ni(bisimpy)MeOH(ReO4)2], (1) (bisimpy = 2,6-bis(4,4,5,5-tetramethyl-4,5-dihydro-1H-imidazol-2-yl-1-oxyl)pyridine) was structurally and magnetically characterized. Due to an effective separation of the molecules in solid the magnetic behavior of 1 differs considerably from that of a related complex studied earlier, the spin carriers in the former having been strongly ferromagnetically coupled even at room temperature. Dynamic behavior of the paramagnetic cation [Ni(bisimpy)(CD3OD)3] in CD3OD solution was studied by 1H NMR. A temperature dependence of the spectrum of 1 has been analyzed using a dynamic NMR approach. It was shown that an interconversion of two conformers is liable for a fast dynamic process occurring in solution of 1 at elevated temperatures. An estimated value of ?G‡(298 K) for this process was found to be of 59 ± 3 kJ/mol. It was confirmed that a considerable extension of the measurable rate constants range compared to that for diamagnetic compounds is a result of the paramagnetic chemical shifts in the Ni complex. Application of paramagnetic d-metal complexes as probes for studying of the free-energy changes in chemical exchange processes, as well as the advantages of this method compared to diamagnetic species are considered. The investigated complex represents an example of the new type of thermometric NMR sensors being to our knowledge is the most temperature sensitive reagent among the d-metal paramagnetic coordination compounds. | ||
| 333 | |a Режим доступа: по договору с организацией-держателем ресурса | ||
| 461 | |t Sensors and Actuators B: Chemical | ||
| 463 | |t Vol. 239 |v [P. 405–412] |d 2017 | ||
| 610 | 1 | |a труды учёных ТПУ | |
| 610 | 1 | |a электронный ресурс | |
| 610 | 1 | |a temperature sensing | |
| 610 | 1 | |a biradical | |
| 610 | 1 | |a iminonitroxide | |
| 610 | 1 | |a nickel(II) | |
| 610 | 1 | |a paramagnetic shift reagent | |
| 610 | 1 | |a температура | |
| 610 | 1 | |a измерение | |
| 610 | 1 | |a бирадикалы | |
| 610 | 1 | |a никель | |
| 701 | 1 | |a Babailov |b S. P. |c chemist |c Senior researcher of Tomsk Polytechnic University |f 1960- |g Sergey Pavlovich |3 (RuTPU)RU\TPU\pers\36566 | |
| 701 | 1 | |a Peresypkina |b E. V. |g Evgeniya Vladimirovna | |
| 701 | 1 | |a Journaux |b Y. |g Yves | |
| 701 | 1 | |a Vostrikova |b K. E. |g Kira Eduardovna | |
| 712 | 0 | 2 | |a Национальный исследовательский Томский политехнический университет (ТПУ) |b Физико-технический институт (ФТИ) |b Кафедра химической технологии редких, рассеянных и радиоактивных элементов (№ 43) (ХТРЭ) |3 (RuTPU)RU\TPU\col\18733 |
| 801 | 2 | |a RU |b 63413507 |c 20171016 |g RCR | |
| 856 | 4 | |u https://doi.org/10.1016/j.snb.2016.08.015 | |
| 942 | |c CF | ||