Crystal structure and magnetic properties of the R₁₁Co₄In₉ compounds (R = Tb–Er) have been investigated by means of X-ray diffraction as well as dc magnetic measurements. The compounds crystallize in the orthorhombic Nd₁₁Pd₄In₉-type crystal structure (Cmmm space group) in which the rare earth atoms occupy five nonequivalent sublattices. Magnetic properties of the investigated compounds are related mainly to the R³⁺ ions. The values of effective magnetic moments in the paramagnetic state are close to the free R³⁺ ion values while the moments in the ordered state at T = 2.0 K (R = Tb, Dy) or T = 1.9 K (R = Ho, Er) and H = 90 kOe are lower than the respective R³⁺ moments. The compounds show complex magnetic properties below 95 K (Tb), 88 K (Dy), 35 K (Ho) and 5.4 K (Er). With increase of temperature the antiferromagnetic ground state changes to the ferro- or ferrimagnetic one. The critical temperatures of magnetic ordering do not fulfill the de Gennes scaling indicating a strong influence of the crystal electric field (CEF) in stabilizing the magnetic order.

R ₁₁ Co ₄ In ₉化合物（R = Tb–Er）的晶体结构和磁性能已通过X射线衍射和直流磁测量进行了研究。这些化合物在正交晶体的Nd ₁₁ Pd ₄ In ₉型晶体结构（Cmmm空间群）中结晶，其中稀土原子占据了五个非等价的亚晶格。所研究化合物的磁性能主要与R ³⁺离子有关。顺磁状态下的有效磁矩值接近自由R ³⁺在T = 2.0 K（R = Tb，Dy）或T = 1.9 K（R = Ho，Er）和H = 90 kOe的有序状态下的力矩小于相应的R ³⁺力矩。这些化合物在95 K（Tb），88 K（Dy），35 K（Ho）和5.4 K（Er）以下显示出复杂的磁性。随着温度的升高，反铁磁性基态变为铁磁性或亚铁磁性状态。磁序的临界温度未达到de Gennes标度，这表明晶体电场（CEF）在稳定磁序方面有很大影响。