硫脲壳聚糖微量银配合物的制备及抑菌活性

由硫脲壳聚糖和微量的AgNO3反应得到硫脲壳聚糖Ag+配合物。 通过红外光谱对其结构进行了表征。 研究了壳聚糖、硫脲壳聚糖、硫脲壳聚糖-Ag+配合物及AgNO3对大肠杆菌和金黄葡萄球菌的抑菌活性,并测定了其最低抑菌浓度(MIC)和最低杀菌浓度(MBC)。 结果表明,硫脲壳聚糖-Ag+配合物的抑菌活性强于壳聚糖和硫脲壳聚糖,且其MIC和MBC均为100 mg/L（游离Ag+含量为0.032 mg/L）,低于AgNO3的MIC和MBC（均为120 mg/L）。     

Keggin结构稀土钼钒磷四元杂多配合物的合成、表征及苯酚羟化制苯二酚的催化活性

合成了5种通式为(NH₄)₁₅[RE(PMo₉V₂O₃₉)₂]·xH₂O(RE=La³⁺,Ce³⁺,Gd³⁺,Y³⁺,Yb³⁺)的稀土钼钒磷四元杂多配合物,并用IR,UV,XRD,ICP,TG-DTA和CV等手段对其结构和性能进行了表征.催化活性实验表明,标题化合物对苯酚过氧化氢羟化制苯二酚反应有良好的催化活性.     

色层法检测王冠化合物对稀土元素的络合能力

本文应用反相纸色层法和静态吸附平衡法检测了王冠化合物与稀土离子之间的络合能力和水相阴离子类型对络合能力的影响。所用的王冠化合物有:B-15-C-5,DB-18-C-6,四氢呋喃丙酮四聚体,DB-18-C-6-甲醛缩聚物和B-15-C-5-甲醛缩聚物。得到如下主要结果:1.不同王冠化合物的络合能力顺序是;B-15-C-5>DB-18-C-6》四氢呋喃丙酮吗聚体,另B-15-C-5-甲醛缩聚物>DB-18-C-6-甲醛缩聚物。2.稀土离子络合能力的顺序是:Sm³⁺Er³⁺=La³⁺(反相纸色层法),Er³⁺>Eu³⁺>La³⁺(吸附平衡法)。3.与不同阴离子缔合的离子对的稳定性顺序是:苦味酸根>三氯代乙酸根>磺基水杨酸根》Cl^-、NO₃^-、ClO₄^-及SO₄⁼。     

Study on the controllable synthesis of SH-MCM-41 mesoporous materials and their adsorption properties of the La3+, Gd3+ and Yb3+

SH-MCM-41 was examined in adsorption and desorption experiments to investigate the adsorption capacities of La³⁺, Gd³⁺ and Yb³⁺ and the reusability.     

稀土-全反式维甲酸-缬氨酸三元配合物的合成、表征及抗肿瘤活性检测

在无水乙醇介质中,合成了4种新型稀土三元固体配合物。 通过红外光谱、紫外光谱、元素分析和TG-DTA等技术手段测试,确定了配合物的化学组成为:REL₂L'·nH₂O (RE:Nd³⁺,Eu³⁺,La³⁺,Sc³⁺;L=全反式维甲酸;L'=L-缬氨酸)。 利用MTT测试法,检测了配合物对体外培养的人肝癌细胞HepG2、人肺癌细胞A549和人宫颈癌细胞Hela生长的影响。 结果表明,4种稀土配合物与稀土硝酸盐、配体全反式维甲酸和L-缬氨酸对3种癌细胞株的生长均有一定的抑制作用,但在一定的浓度范围内,三元固体配合物的抑制效果明显优于稀土硝酸盐和2种配体;稀土配合物对3种癌细胞株生长的抑制作用基本上随浓度的升高而增强,存在一定的时间依赖性和浓度依赖性。 为了进一步阐明抗肿瘤作用的原因,利用光谱方法和黏度法的手段,对配合物与DNA之间的相互作用方式做了考察,推测配合物抗肿瘤活性的起效与这种嵌入DNA双螺旋结构的作用方式有关。     

镧系元素Dawson结构钨钒磷四元杂多配合物的合成、表征以及对H2O2分解的催化活性

合成了通式为K₁₅H₃[Ce(P₂W₁₆VO₆₁)₂]·61H₂O、K₁₅H₄[Ln(P₂W₁₆VO₆₁)₂]·xH₂O(Ln=La³⁺,Pr³⁺,Nd³⁺,Sm³⁺,Eu³⁺,Gd³⁺,Dy³⁺,Yb³⁺)的9种镧系元素Dawson结构的钨钒磷四元杂多配合物,并用IR、UV、NMR、ESR、XRD、TG-DTA等对其结构和性质进行了研究。该类配合物具有与K₁₆[Ce(P₂W₁₇VO₆₁)₂]·50H₂O类似的结构,对H₂O₂分解有较高的催化活性。     

表面活性剂存在下铽-镥(钆、钇)-乙酰水杨酸共发荧光体系的研究

本文研究了镥等三种稀土离子与铽-乙酰水杨酸配合物产生的共发荧光效应。在最佳条件下,Lu³⁺、Gd³⁺、Y³⁺的存在可使铽-乙酰水杨酸配合物的荧光分别增强108,58和73倍。讨论了共发光体系的形成条件和荧光特性。利用Tb-Lu-乙酰水杨酸体系和Tb-Lu-乙酰水杨酸-乙二胺四乙酸-十六烷基三甲基溴化铵体系分析了合成稀土样品和包头稀土标准氧化物中的铽,结果满意,加标回收率为90.5～105.6%,并对共发光的机理和表面活性剂的作用进行了初步探讨。     

稀土-二苯甲酰甲烷、邻菲咯啉固态配合物及其掺杂硅胶共发光效应的光声光谱研究

合成了Eu(Dbm)₃·Phen同核和Eu_0.8Ln_0.2(Dbm)₃·Phen(Ln:Er³⁺,Y³⁺)异核固体配合物微晶粉末及其掺杂的SiO2凝胶样品,在300～800nm范围内测定了其光声光谱.结果表明,配合物Eu_0.8Er_0.2(Dbm)₃·Phen,Eu(Dbm)₃·Phen和Eu_0.8Y_0.2(Dbm)₃·Phen配体吸收处的光声强度依次减弱;而Eu_0.8Y_0.2(Dbm)₃·Phen和Eu(Dbm)₃·Phen配合物掺杂的凝胶则情况相反.研究发现,光声强度与稀土配合物分子中能量传递过程相关,Er³⁺,Y³⁺离子的引入改变了三元配合物的弛豫过程,且配合物在粉末状态和凝胶状态的弛豫历程不尽相同.结合荧光光谱,从无辐射跃迁和辐射跃迁的角度分析了标题化合物在两种不同固体状态下的发光性质.     

铕(Ⅲ)荧光增敏体系在微乳液中的发光性质和荧光衰减动力学研究

利用稳态和瞬态光谱方法研究了不同铕离子发光体系中各种因素对铕离子发光性质的影响.通过吸收和激发光谱的变化分析了稀土离子Gd³⁺对Eu³⁺增敏机理,并从荧光衰减动力学角度证明了主配体噻吩甲酰三氟丙酮(TTA)、协配体邻啡咯啉(Phen)、稀土离子Gd³⁺和表面活性剂TX-100对铕离子发光的增敏作用.4种发光体系Eu³⁺/Gd³⁺/TTA/Phen/TX-100,Eu³⁺/TTA/Phen/TX-100,Eu³⁺/Gd³⁺/TTA/Phen和Eu³⁺/Gd³⁺/TTA/TX-100中铕离子⁵D₀态的发光寿命依次为980>670>400>260μs,而且存在铕离子⁵D₁到⁵D₀的传能过程.在发光越强的体系中,⁵D₁的衰减越慢,相应地⁵D₀的上升时间也就越长.研究结果表明,在最佳发光体系中既存在分子内的能量转移,又存在分子间的能量传递.     

钇(Ⅲ)、铽(Ⅲ)、铒(Ⅲ)对氨基苯甲酸配合物共掺杂二氧化硅的光声光谱研究

合成了Tb(p-ABA)₃·H₂O和Ln(p-ABA)₃·H₂O(p-ABA: 对氨基苯甲酸, Ln: Y或Er)配合物共掺杂的SiO₂样品. 荧光光谱测定结果表明, Y(p-ABA)₃·H₂O的引入增强了样品中Tb³⁺离子的特征发光, 而Er(p-ABA)₃·H₂O的引入使Tb³⁺的发光减弱. 光声光谱结果表明, 与Tb³⁺配合物单掺的样品相比, Tb³⁺和Y³⁺配合物共掺样品的光声强度降低; 而Tb³⁺和Er³⁺配合物共掺的样品则情况相反. 实验测定了共掺杂样品的相对量子发光效率和发光寿命, 从无辐射跃迁和辐射跃迁的角度提出共发光效应可能的机制. 结合对室温下陈化干燥样品的分析发现, 只有经适当的热处理过程才能在SiO₂凝胶中形成具有多核结构的稀土配合物.     

儿茶素-银纳米复合材料的制备及其应用

探索了以植物活性成分儿茶素作为还原剂和保护剂一步水热法合成儿茶素-银纳米复合材料,并进一步测试了纳米复合材料的抑菌活性。 紫外可见吸收光谱(UV-Vis)和红外光谱(FTIR)测定证明制备得到了儿茶素包裹的银纳米粒子。 透射电子显微镜(TEM)和X射线衍射(XRD)结果显示银纳米粒子的平均粒径为22.7 nm,并具有面心立方晶体结构。 抑菌活性实验结果表明,儿茶素-银纳米复合粒子对大肠杆菌、金黄色葡萄球菌以及白色念球菌都有很强抑制作用,尤其对白色念球菌的抑制作用最强,其最低抑制浓度(MIC)和最低杀菌浓度(MBC)分别为19.63和39.26 μg/mL。 儿茶素-银纳米粒子强抑菌活性可归因于其表面银离子的持续释放,有望应用于长效抑菌制剂产品。     

聚(ε-己内酯)-多肽共聚物胶束增强抗生素的抗菌活性

Bacterial infection is a major threat to human health, and can cause several diseases including gastroenteritis, influenza, tetanus, and tuberculosis. As conventional antibiotic treatment may cause various undesirable effects such as stomach disorder and bacterial resistance, it is necessary to improve the antibacterial efficiency of antibiotics. Here, we synthesized a peptide-based copolymer, poly(ε-caprolactone)-block-poly(glutamic acid)-block-poly(lysine-stat-phenylalanine)[PCL₃₄-b-PGA₃₀-b-P(Lys₁₆-stat-Phe₁₂)] by ring-opening polymerization (ROP) of ε-caprolactone and amino acid N-carboxyanhydride (NCA). Successful synthesis of the copolymer was verified by proton nuclear magnetic resonance and size exclusion chromatography. This copolymer can self-assemble into negatively charged micelles (-26.7 mV) under alkaline conditions by solvent switch method. The micelle structure was confirmed by transmission electron microscopy and dynamic light scattering, and revealed to have a diameter of ~42 nm. Antibiotics were loaded into micelles during the self-assembly process, and cell viability assay was conducted to evaluate its cytotoxicity with and without tobramycin. No obvious cytotoxicity was observed for both micelles when the concentration was lower than 300 μg·mL^-1. The antibiotic-loaded micelles demonstrated very low minimum inhibitory concentrations (MICs) against both Gram-negative Escherichia coli (E. coli) (7.8 μg·mL^-1) and Gram-positive Staphylococcus aureus (S. aureus) (18.2 μg·mL^-1), while the MICs of free tobramycin were 3.9 and 1.0 μg·mL^-1, respectively. The drug-loading content and efficiency of the micelles were 5.2% and 24.3%, respectively. Therefore, the MICs of the loaded tobramycin against E. coli and S. aureus were 0.4 and 0.9 μg·mL^-1, respectively, suggesting that the micelle could enhance the antibacterial activity of antibiotics. Tobramycin-loaded micelles demonstrated a sustained release characteristic, with 85% of the antibiotics released after 8 h. In bacteria-induced acidic microenvironment, the coil conformation of PGA blocks transforms and PGA blocks shrink toward the micelle core. Concomitantly, the carboxyl side chains are protonated in an acidic environment, increasing the hydrophobicity of this micelle. Antibiotics will be captured when reaching the outer core to slow down the releasing process. Furthermore, the poly(lysine-stat-phenylalanine) [P(Lys-stat-Phe)] coronas with broad spectrum intrinsic antibacterial activity can penetrate the bacterial cell membrane, leading to leakage of the cellular contents of the bacteria and ultimately their death. Due to the sustained release property of micelle and the intrinsic activity of the antibacterial peptide segments, this micelle can greatly enhance the antibacterial activity of antibiotics. Overall, this antibiotic-loaded micelle provides a novel approach for significantly reducing the antibiotics dosage and avoiding the associated health risks.     

钆离子:周期表中最高自旋的离子

钆离子是元素周期表中自旋值最大的离子,其轨道角动量被完全淬灭,具有十分特殊的电子结构。本文以核磁共振造影剂以及分子自旋量子比特为例介绍了钆离子在前沿科技中的应用。     

三维无溶剂含能Ag-MOF的制备、热分解动力学及爆炸性能

Solvent molecules can significantly reduce the heat of detonation and stability of energetic metal-organic framework (EMOF) materials, and the development of solvent-free EMOFs has become an effective strategy to prepare high-energy density materials. In this study, a solvent-free EMOF, [Ag₂(DTPZ)]_n (1) (N% = 32.58%), was synthesized by reacting a high-energy ligand, 2, 3-di(1H-tetrazol-5-yl)pyrazine (H₂DTPZ), with silver ions under hydrothermal conditions, and it was structurally characterized by elemental analysis, infrared spectroscopy, X-ray diffraction, and thermal analysis. In 1, the DTPZ²⁻ ligands that adopted a highly torsional configuration bridged the Ag⁺ ions in an octadentate coordination mode to form a three-dimensional framework (ρ = 2.812 g∙cm⁻³). The large steric effect and strong coordination ability of DTPZ²⁻ effectively prevented the solvent molecules from binding with the metal centers or occupying the voids of 1. Moreover, the strong π-π stacking interactions [centroid-centroid distance = 0.34461(1) nm] between the tetrazole rings in different DTPZ²⁻ ligands provided a high thermal stability to the framework (T_e = 619.1 K, T_p = 658.7 K). Thermal analysis showed that a one-step rapid weight loss with intense heat release primarily occurred during the decomposition of 1, suggesting potential energetic characteristics. Non-isothermal thermokinetic analyses (based on the Kissinger and Ozawa-Doyle methods) were performed using differential scanning calorimetry to obtain the thermoanalysis kinetic parameters of the thermodecomposition of 1 (E_a = 272.1 kJ·mol⁻¹, E_o = 268.9 kJ·mol⁻¹; lgA =19.67 s⁻¹). The related thermodynamic parameters [enthalpy of activation (ΔH^≠ = 266.9 kJ·mol⁻¹), entropy of activation (ΔS^≠ = 125.4 J·mol⁻¹·K⁻¹), free energy of activation (ΔG^≠ = 188.3 kJ·mol⁻¹)], critical temperature of thermal explosion (T_b = 607.1 K), and self-accelerating decomposition temperature (T_SADT = 595.8 K) of the decomposition reaction were also calculated based on the decomposition peak temperature and extrapolated onset temperature when the heating rate approached zero. The results revealed that 1 featured good thermal safety, and its decomposition was a non-spontaneous entropy-driven process. The standard molar enthalpy for the formation of 1 was calculated to be (2165.99 ± 0.81) kJ·mol⁻¹ based on its constant volume combustion energy determined using a precise rotating oxygen bomb calorimeter. Detonation and safety performance tests revealed that 1 was insensitive to impact and friction, and its heat of detonation (10.15 kJ·g⁻¹) was higher than that of common ammonium nitrate explosives, such as octogen (HMX), hexogene (RDX), and 2, 4, 6-trinitrotoluene (TNT), indicating that 1 is a promising high-energy and insensitive material.     

负载型铼催化剂体系与甲醇选择氧化性能的关系

以铼酸铵为前驱体,制备了氧化物负载型铼催化剂并研究其甲醇选择氧化反应的催化性能.结果表明,Fe₂O₃和V₂O₅等氧化物负载型铼催化剂表现出很高的甲醇选择氧化制备二甲氧基甲烷的催化性能,选择性可达90%～94%(摩尔分数).选择氧化反应活性与铼担载量有关.在α－Fe₂O₃担载的铼催化剂中,以担载质量分数为1%～3%铼的催化剂活性最高[450mmol/(h·gRe)],而高于3%的铼担载量,单位铼催化活性逐渐下降.XRD,XPS和脉冲反应等结果表明,铼酸铰负载于α-Fe₂O₃载体上,并于He气氛中焙烧后,所得表面铼物种与担载量有关,当低于单层担载量时以Re⁶⁺占主导,而高于单层担载量时则Re⁶⁺与Re⁴⁺物种共存.     

三氮唑取代杯[4]芳烃配位聚合物的合成与荧光性能

利用四[1-(1, 2, 4-三氮唑基)甲基]间苯二酚杯[4]芳烃配体(TTR4A)在溶剂热的条件下合成了两个配位聚合物,[[Zn₂(TTR4A)(L)₂]·DMF·4H₂O]_n(化合物1) (DMF = N, N-二甲基甲酰胺)和[[Co(TTR4A)Cl₂]·DMA·H₂O]_n (化合物2) (H₂L = 4, 4’-联苯二甲酸) (DMA = N, N-二甲基乙酰胺)。通过单晶X射线衍射方法对这两个配位聚合物的结构进行了确定。利用红外、元素分析、粉末X射线衍射(PXRD)和热重表征手段对化合物1和2进行了表征。在化合物1中,四个L配体连接着四个Zn(Ⅱ)离子形成了环状的Zn₄L₄结构单元,该结构单元进一步地被TTR4A链接形成了一维链状结构。在化合物2中,TTR4A的四个三氮唑基团各连接一个Co(Ⅱ)离子形成二维层状结构。此外,我们对化合物1的荧光性能进行了研究,荧光测定表明固态条件下化合物1发出很强的荧光,并能够选择性地对Fe³⁺、Cr₂O₇²⁻和硝基苯分子产生响应。     

锂金属负极的可逆性与沉积形貌的关联

高能量密度二次电池的商业化将会推动便携式电子设备和电动车的飞速发展。锂金属电池因具有较高的理论能量密度而受到研究者的广泛关注。然而,锂金属负极较低的库仑效率(CE)和枝晶生长等问题,严重制约了锂金属电池的发展。库仑效率是衡量电池体系可逆性的关键参数之一,锂金属负极的库仑效率在不同电解液中存在较大的差异,本文以四种常见的电解液为例,包括1 mol·L^-1六氟磷酸锂-碳酸乙烯酯/碳酸二甲酯电解液,1 mol·L^-1六氟磷酸锂-碳酸乙烯酯/碳酸二甲酯+5%(w)氟代碳酸乙烯酯电解液,1 mol·L^-1双(三氟甲烷磺酰)亚胺锂-乙二醇二甲醚/1,3二氧戊环+2%(w)硝酸锂电解液,以及4 mol·L^-1双氟磺酰亚胺锂-乙二醇二甲醚电解液,利用原子力显微镜研究了不同电解液体系中锂金属的生长行为,探讨了锂金属沉积形貌与其库仑效率之间的联系,为发展高效的锂金属负极提供了参考依据。     

CoFe2O4/CuO活化过氧乙酸高效降解磺胺甲恶唑(英文)

利用化学沉淀法和溶胶凝胶法,通过两步法成功制备出含有尖晶石钴铁氧体和氧化铜的复合催化剂CoFe₂O₄/CuO,通过扫描电子显微镜(SEM)、X射线光电子能谱(XPS)和X射线衍射(XRD)对制备出的CoFe₂O₄/CuO进行表征,探究不同高级氧化体系对磺胺甲恶唑(SMX)去除能力,考察过氧乙酸(PAA)浓度、催化剂投加量、水体中常见干扰物质(Cl^-,HCO-3,SO₄^2-,HA)和不同自由基捕获剂对SMX去除的影响。分析结果表明CoFe₂O₄/CuO同时具有CoFe₂O₄与CuO的特征,对比单独CoFe₂O₄与CuO,CoFe₂O₄/CuO对PAA展现出极高的活化性能,在最佳反应条件下(催化剂投加量=20mg·L^-1,c(PAA)=200μ...     

基于三维多孔活性炭构筑安全、高性能以及长循环寿命的锌离子混合电容器

可充电水系锌离子电池因成本低、环境友好等优点,已经成为目前电化学储能领域的研究热点之一。然而锌离子电池中高容量、长循环寿命的阴极材料的开发仍然是一大难题。为了解决这一问题,本文中通过直接利用锌片做阳极和集流体,采用高比表面积的三维多孔活性炭(3DAC)做阴极构筑了一种锌离子混合电容器(ZIHC)。该ZIHC器件表现出了优异的电化学性能,具有目前文献报道的ZIHC最高的213 mAh·g~(-1)比容量,展示出164Wh·kg~(-1)的高能量密度和9.3kW·kg~(-1)的高功率密度以及优异的循环稳定性(10 A·g~(-1)下循环20000圈之后,容量保持率为90%,库伦效率接近100%)。我们认为这种采用高比表、三维多孔活性炭(3DAC)做阴极构筑的安全、高性能以及长寿命的水系锌离子混合电容器将为下一代高性能储能器件的开发提供新的研究思路。     

2, 4, 6-三甲基苯甲酸与5, 5'-二甲基-2, 2'-联吡啶构筑的系列镧系超分子配合物的晶体结构、热分解机理和性能

Six ternary lanthanide complexes formulated as [Ln(2, 4, 6-TMBA)₃(5, 5'-DM-2, 2'-bipy)]₂ (Ln = Pr 1, Nd 2, Sm 3, Eu 4, Gd 5, Dy 6; 2, 4, 6-TMBA = 2, 4, 6-trimethylbenzoate; 5, 5'-DM-2, 2'-bipy = 5, 5'-dimethyl-2, 2'-bipyridine) have been synthesized under solvothermal conditions and characterized by single-crystal X-ray diffraction, elemental analysis, thermogravimetric analysis, etc. The results of crystal diffraction analysis show that complexes 1–6 are binuclear units, crystallizing in the triclinic Pī space group. Complexes 1–5 are isostructural, and each of the central metal ions has a coordination number of 9. The asymmetric unit of complexes 1–5 consists of one Ln³⁺, one 5, 5'-DM-2, 2'-bipy ligand, and three 2, 4, 6-TMBA^- moieties with three coordination modes: chelation bidentate, bridging bidentate, and bridging tridentate. The coordination geometry of Ln³⁺ is distorted monocapped square antiprismatic. The binuclear units of complexes 1–5 form a one-dimensional (1D) supramolecular chain along the c-axis via π–π stacking interactions between the 2, 4, 6-trimethylbenzoic acid rings. The 1D chains are linked to form a supramolecular two-dimensional (2D) sheet in the bc plane via π–π stacking interactions between the pyridine rings. Although the molecular formulae of complex 6 and complexes 1–5 are similar, the coordination environment of the lanthanide ions is different in the two cases. The asymmetric unit of complex 6 contains a Dy³⁺ ion coordinated by a bidentate 5, 5'-DM-2, 2'-bipy and three 2, 4, 6-TMBA^- ligands adopting bidentate and bridging bidentate coordination modes. The Dy³⁺ metal center has a coordination number of 8, with distorted square antiprismatic molecular geometry. The binuclear molecule of 6 is assembled into a six-nuclear unit by π–π weak staking interactions between two 5, 5'-DM-2, 2'-bipy ligands; then, adjacent six-nuclear units form a 1D chain via offset π–π interactions between 5, 5'-DM-2, 2'-bipy ligands on different adjacent units. The adjacent 1D chains are linked by C―H···O hydrogen bonding interactions to form a 2D supramolecular structure. The thermal stability and thermal decomposition mechanism of all the complexes are investigated by the combination of thermogravimetry and infrared spectroscopy (TG/FTIR) techniques under a simulated air atmosphere in the temperature range of 298–973 K at a heating rate of 10 K·min^-1. Thermogravimetric studies show that this series of complexes have excellent thermal stability. During the thermal decomposition of the complex, the neutral ligand is lost first, followed by the acid ligand, and finally, the complex is decomposed into rare earth oxides. The three-dimensional infrared results are consistent with the thermogravimetric results. The photoluminescence spectra of complex 4 show the strong characteristic luminescence of Eu³⁺. The five typical emission peaks at 581, 591, 621, 651, and 701 nm correspond to the ⁵D₀ → ⁷F₀, ⁵D₀ → ⁷F₁, ⁵D₀ → ⁷F₂, ⁵D₀ → ⁷F₃, and ⁵D₀ → ⁷F₄ electronic transitions of Eu³⁺, respectively. The emission at 621 nm is due to the electric dipole transition ⁵D₀ → ⁷F₂, while that at 591 nm is assigned to the ⁵D₀ → ⁷F₁ the magnetic dipole transition. The lifetime (τ) of complex 4 is calculated as 1.15 ms based on the equation τ = (B₁τ₁² + B₂τ₂²))/(B₁τ₁ + B₂τ₂), and the intrinsic quantum yield is calculated to be 45.1%. Further, the magnetic properties of complex 6 in the temperature range of 2–300 K are studied under an applied magnetic field of 1000 Oe.