Crystal structure and ferromagnetic phase transitions in CeCu$_{1-x}$Ge$_{1+x}$ (0.0$\mathbin{\lower.3ex\hbox{$\buildrel<\over {\smash{\scriptstyle=}\vphantom{_x}}$}}$$x\mathbin{\lower.3ex\hbox{$\buildrel<\over {\smash{\scriptstyle=}\vphantom{_x}}$}} $0.3)

As revealed in the powder x-ray diffraction and crystallographic data, the single phase sample in the series CeCu$_{1-x}$Ge$_{1+x}$ (0.0$\mathbin{\lower.3ex\hbox{$\buildrel<\over {\smash{\scriptstyle=}\vphantom{_x}}$}} $$x\mathbin{\lower.3ex\hbox{$\buildrel<\over {\smash{\scriptstyle=}\vphantom{_x}}$}} $0.3) crystallizes in the AlB$_{2}$-type structure with space group P6/mmm. The maximum ferromagnetic transition temperature T$_{c}$ in CeCu$_{1-x}$Ge$_{1+x}$, as determined from the electrical- resistivity and magnetic susceptibility measurements, is 10.6 K for the compound CeCu$_{0.8}$Ge$_{1.2}$. The magnetic susceptibility for each sample in CeCu$_{1-x}$Ge$_{1+x}$ (0.0$\mathbin{\lower.3ex\hbox{$\buildrel<\over {\smash{\scriptstyle=}\vphantom{_x}}$}} $$x\mathbin{\lower.3ex\hbox{$\buildrel<\over {\smash{\scriptstyle=}\vphantom{_x}}$}} $0.3) follows Curie's behavior between 100 and 300 K with an effective moment 2.6$\pm $0.1 $\mu _{B}$/Ce atom, a value close to that of Ce$^{3+}$. However, the observed saturation magnetic moment values (0.96 $\sim $ 1.15 $\mu _{B})$ at low temperatures for all these compounds are well less than the theoretically expected value 2.14 $\mu _{B}$ for the free Ce$^{3+}$ ion tangling the entire six-fold J = 5/2 multiplet. Subtracting the estimated phonon contribution from LaCuGe, the entropy associated with the magnetic structure of CeCuGe is found to meet the theoretical value of Rln2, which would be expected for a doublet ground state of Ce$^{3+}$ ion in the compound CeCuGe. The reduced saturation moment in CeCu$_{1-x}$Ge$_{1+x}$ is reasonably ascribed to partial lifting of the 4f-electron level degeneracy.