Vestnik of the Far East Branch of the Russian Academy of SciencesVestnik of the Far East Branch of the Russian Academy of SciencesВестник Дальневосточного отделения Российской академии наук0869-7698The Russian Academy of Sciences67605510.31857/S0869769824010099leevvqChemical Sciences. Physical methods of materials researchХимические науки. Физические методы исследования материаловResearch ArticleElectron paramagnetic resonance on impurity copper ions in sodium trititanate with a hierarchical two-level architectureЭлектронный парамагнитный резонанс на примесных ионах меди в трититанате натрия с иерархической двухуровневой архитектуройhttps://orcid.org/0009-0006-2195-1042SaritskyDenis A.СарицкийДенис Алексеевич
Russian Federation

Junior Researcher

младший научный сотрудник

denissaricki@mail.ruhttps://orcid.org/0000-0001-7917-9207ZiatdinovAlbert M.ЗиатдиновАльберт Муктасимович
Russian Federation

Doctor of Sciences in Physics and Mathematics, Chief Researcher, Head of the Laboratory

доктор физико-математических наук, главный научный сотрудник, заведующий лабораторией

ziatdinov@ich.dvo.ruZheleznovVeniamin V.ЖелезновВениамин Викторович
Russian Federation

Doctor of Sciences in Chemistry, Leading Researcher

доктор химических наук, ведущий научный сотрудник

zhvv53@mail.ruhttps://orcid.org/0000-0003-4337-5550OpraDenis P.ОпраДенис Павлович
Russian Federation

Candidate of Sciences in Chemistry, Senior Researcher, Head of the Laboratory

кандидат химических наук, старший научный сотрудник, заведующий лабораторией

dp.opra@gmail.comhttps://orcid.org/0000-0003-1576-8680GnedenkovSergey V.ГнеденковСергей Васильевич
Russian Federation

Corresponding Member of the RAS, Doctor of Sciences in Chemistry, Professor, Director

член-корреспондент РАН, доктор химических наук, профессор, директор

svg21@hotmail.comInstitute of Chemistry FEB RASИнститут химии ДВО РАН15022024112614328022025Copyright ©; 2024, Russian Academy of SciencesCopyright ©; 2024, Российская академия наук2024Russian Academy of SciencesРоссийская академия наукhttps://journals.eco-vector.com/0869-7698/article/view/676055

The results of studies of electron paramagnetic resonance on impurity copper ions in sodium trititanate (Na2Ti3O7) with a hierarchical two-level architecture, potentially suitable for use as negative electrodes of sodium-ion batteries, are presented. The main emphasis in the work was placed on the identification of magnetically different centers of the impurity copper ion, establishing the positions of these centers in the crystal lattice, determining the nature of their distributions in the volume of the sample, and elucidating the charge compensation mechanism for aliovalent substitutions. For Cu2+ ions in positions of Ti4+ substitution, the degree of a spin density delocalization from the bottom dx2-y2 orbital to the σ-orbitals of the nearest equatorial oxygen ions was estimated.

Представлены результаты исследований электронного парамагнитного резонанса на примесных ионах меди в трититанате натрия (Na2Ti3O7) с иерархической двухуровневой архитектурой, потенциально пригодного для использования в качестве отрицательных электродов натрий-ионных аккумуляторов. Основной акцент в работе был сделан на выявление магнитно-неэквивалентных центров примесного иона меди, установление позиций этих центров в кристаллической решетке, определение характера их распределений в объеме образца, а также на выяснение механизмов зарядовой компенсации при алиовалентных замещениях. Для ионов Cu2+ в позициях замещения Ti4+ была оценена делокализация спиновой плотности с нижней атомной орбитали dx2-y2 на σ-орбитали ближайших экваториальных ионов кислорода.

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