chemicallytechFine Chemical TechnologiesТонкие химические технологии2410-65932686-7575MIREA – Russian Technological University (RTU MIREA).10.32362/2410-6593-2024-19-5-452-461XAJTFBchemicallytech-2163Research ArticleCHEMISTRY AND TECHNOLOGY OF INORGANIC MATERIALSХИМИЯ И ТЕХНОЛОГИЯ НЕОРГАНИЧЕСКИХ МАТЕРИАЛОВOptical and surface properties of Schiff base ligands and Cu(II) and Co(II) complexesОптические и поверхностные свойства лигандов на базе оснований Шиффа и комплексов Cu(II) и Co(II)https://orcid.org/0000-0002-2600-2448РашидАла АднанRashadAlaa Adnan

Ала Аднан Рашид, ассистент преподавателя, кафедра химии

Джадрия, Багдад

Scopus Author ID 57209788535

Alaa Adnan Rashad - Assistant Teacher, Master Degree

Jadriya, Baghdad

Scopus Author ID 57209788535

Scopus Author ID 57209788535

alaa.adnan@nahrainuniv.edu.iqhttps://orcid.org/0000-0002-7903-7599НаджибДина А.NajeebDina A.

Дина А. Наджиб, доцент, кафедра химии, Научный колледж

Джадрия, Багдад

Scopus Author ID 57189488023

Dina A. Najeeb - Associate Professor, Master Degree

Jadriya, Baghdad

Scopus Author ID 57189488023

dina.najeeb@nahrainuniv.edu.iqhttps://orcid.org/0000-0002-2890-5448МахмудШаймаа М.MahmoudShaymaa M.

Шаймаа М. Махмуд, ассистент преподавателя

Джадрия, Багдад

Scopus Author ID 58062049600

Shaymaa M. Mahmoud - Assistant Teacher, Master Degree

Jadriya, Baghdad

Scopus Author ID 58062049600

shaymaa.ali@nahrainuniv.edu.iqhttps://orcid.org/0000-0002-0150-6543АкрамЭвонAkramEvon

Эвон Акрам, преподаватель

Джадрия, Багдад

Scopus Author ID 7191172531

Evon Akram Abd-Aljabar - Teacher, Master Degree

Jadriya, Baghdad

Scopus Author ID 57191172531

evon.akram@nahrainuniv.edu.iqhttps://orcid.org/0000-0003-3829-5783Зайн уль АбдинХалидZainulabdeenKhalid

Халид Зайн уль Абдин, PhD, преподаватель

Джадрия, Багдад

Scopus Author ID 57223028460

Khalid Zainulabdeen - Teacher, PhD

Jadriya, Baghdad

Scopus Author ID 57223028460

khalid_1chem1@yahoo.comhttps://orcid.org/0000-0003-2936-9373ДулаймиСаламDulaimSalam

Салам Дулайми, PhD, преподаватель

Джадрия, Багдад

Scopus Author ID 57220069401

Salam Dulaimi - Teacher, PhD

Jadriya, Baghdad

Scopus Author ID 57220069401

Salamdulaimi82@gmail.comhttps://orcid.org/0000-0002-8843-8677ЮсопРахими М.YusopRahimi M.

Рахими М. Юсоп, PhD, доцент

43600 Банги, Селангор

Scopus Author ID 36994895800

Rahimi M. Yusop -Professor Ts., PhD

43600 Bangi, Selangor

Scopus Author ID 36994895800

drmc@ukm.edu.myНаучный колледж, Университет Аль‐НахрейнИракCollege of Science, Al-Nahrain UniversityIraqНаучный колледж, Университет Аль-НахрейнИракCollege of Science, Al-Nahrain UniversityIraqНаучно-исследовательский и учебный центр судебной экспертизы ДНК, Университет Аль-НахрейнИракForensic DNA Research and Training Center, Al-Nahrain UniversityIraqШкола химических наук и пищевых технологий, Университет КебангсаанМалайзияSchool of Chemical Science and Food Technology, University Kebangsaan MalaysiaMalaysia202404112024195452461Copyright © Rashad A.A., Najeeb D.A., Mahmoud S.M., Akram E., Zainulabdeen K., Dulaim S., Yusop R.M., 20242024Рашид А.А., Наджиб Д.А., Махмуд Ш.М., Акрам Э., Зайн уль Абдин Х., Дулайми С., Юсоп Р.М.Rashad A.A., Najeeb D.A., Mahmoud S.M., Akram E., Zainulabdeen K., Dulaim S., Yusop R.M.Данная работа распространяется под лицензией Creative Commons Attribution 4.0.This work is licensed under a Creative Commons Attribution 4.0 License.https://www.finechem-mirea.ru/jour/article/view/2163

Objectives. To study the transition of electrons in 1,2-phenyl(4’-carboxy)benzylidene Schiff base ligand and transition metal ions, optical properties, as well as the surface chemistry of supported transition metals using diffuse reflectance spectroscopy (DRS); to study the roughness and morphology of the Schiff base ligand and its complexes using atomic force microscopy (AFM).Methods. DRS, AFM, and Fourier-transform infrared spectroscopy instruments were used to identify electron transitions, optical properties, and surface morphology in Schiff base ligands and their complexes.Results. The DRS revealed the d–d transitions and charge transfer shifts of all compounds, and helped identify the structure of the ligand. One of the optical properties studied was the energy gap calculation of the ligand and its complexes. The copper complex exhibited more semiconducting behavior with surface morphology properties such as surface roughness parameters lower than those of the ligand and the cobalt complex. This can be attributed to the smaller size of the copper atom, as well as lower electron transitions compared to the cobalt complex and the square planar bonding shape.Conclusions. In Schiff base ligands, the reflectance spectrum bands reveal three electron transitions: n→π*, π→π*, and σ→σ* transitions. In cobalt complexes, four transitions are indicated: 4A2(F)→4T1(F), 4A2(F)→4T1(P), charge transfer bands, and tetrahedral geometry. Copper complexes exhibit three transitions: 2B1g→2A1g, 2B1g→2Eg, and charge transfer bands, with a square planar geometry for their structure. The energy gap calculations were 2.42, 2.29, and 2.30 eV, respectively. In the case of the SH ligands, copper complexes, and cobalt complexes, all compounds exhibited semiconductor properties. However, the complexes displayed increased conductivity due to the influence of the metal and coordination structure.

Цели. Изучить переход электронов в 1,2-фенил(4’-карбокси)бензилиденовом лиганде основания Шиффа и в ионах переходных металлов, оптические свойства, а также химический состав поверхности нанесенных переходных металлов с помощью спектроскопии диффузного отражения (СДО); изучить шероховатость и морфологию лиганда на базе основания Шиффа и комплексов на его основе с использованием атомно-силовой микроскопии (АСМ).Методы. Для идентификации электронных переходов, анализа оптических свойств и морфологии поверхности лигандов на базе оснований Шиффа и их комплексов были использованы СДО, АСМ и инфракрасная спектроскопия с преобразованием Фурье.Результаты. СДО выявила d–d переходы и сдвиги в переносе заряда во всех соединениях и помогла идентифицировать структуру лиганда. Одним из изученных оптических свойств был расчет энергетической щели лиганда и его комплексов. Комплекс меди показал более ярко выраженные полупроводниковые свойства, в то время как морфологические свойства поверхности, такие как шероховатость, у комплекса меди были ниже, чем у лиганда и комплекса кобальта. Это можно объяснить меньшим размером атома меди, более низкими электронными переходами по сравнению с комплексом кобальта, а также плоскоквадратной геометрией.Выводы. В лигандах на базе оснований Шиффа полосы спектра отражения обнаруживают три электронных перехода: n→π*, π→π* и σ→σ*. В комплексах кобальта выявлены переходы 4A2(F)→4T1(F), 4A2(F)→4T1(P), полосы переноса заряда и тетраэдрическая геометрия. Комплексы меди демонстрируют переходы 2B1g→2A1g, 2B1g→2Eg и полосы переноса заряда, при этом структура комплексов меди имеет плоскоквадратную геометрию. Расчеты энергетического зазора составили 2.42, 2.29 и 2.30 эВ соответственно. В случае лигандов SH, комплексов меди и кобальта все соединения проявляли полупроводниковые свойства. Однако комплексы меди и кобальта проявляли повышенную проводимость из-за наличия металла и координационной структуры.

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The authors declare that there are no conflicts of interest present.