The title compound, 1,5,5-trimethyl-imidazolidine-2,4-dione was characterized by FT-IR, ¹H-NMR, and ¹³C-NMR spectroscopy techniques. The crystal structure was established by single-crystal X-ray diffraction. The powder X-ray powder diffraction analysis confirms the phase purity of the crystalline sample. The hydantoin with formula C₆H₁₀N₂O₂ crystallizes in the tetragonal space group I4/m (N°87), Z= 8, and unit cell parameters a= 15.554(2) Å, c= 6.623(6) Å. This space group is very infrequent to find in purely organic molecules and is since, in the asymmetric unit, the hydantoin ring lies on a mirror plane m. The crystalline packing is stabilized by the formation of intermolecular interactions of the strong hydrogen bond type of the N–H···O between the neighboring hydantoin rings. In addition, the crystalline structure presents the formation of weaker unconventional hydrogen bonds of the C–H···O type. These hydrogen bonds give rise to the formation of 8, 24, and 36-membered ring-type supramolecular structures described by the graphs R²₂(8), R⁴₄(24), and R⁸₈(36), respectively, which govern the packing of the supramolecular structure of 1,5,5-trimethyl-imidazolidine-2,4-dione.

Hirshfeld surface analysis of the crystal structure shows that the most important contributions for the crystal packing are from H···H (58.3%) and H··O/O··H (34.0%) interactions, which indicate that van der Waals interactions are the dominant forces in the crystal packing. Energy framework calculations suggest that the contacts formed between molecules are slightly electrostatic.

These intermolecular interactions were also investigated through topological analysis of the electron density (ρ) employing the NCI method. Experimental and theoretical results obtained for this new hydantoin compound suggest that N–H···O and C–H···O interactions play an important role in the stabilization of its supramolecular structure.

^{通过FT-IR、 1} H-NMR和¹³ C-NMR光谱技术对标题化合物1,5,5-三甲基-咪唑烷-2,4-二酮进行表征。通过单晶X射线衍射建立了晶体结构。粉末X射线粉末衍射分析证实了晶体样品的相纯度。化学式为C ₆ H ₁₀ N ₂ O ₂的乙内酰脲在四方空间群I 4/ m (N°87)中结晶，Z= 8，晶胞参数a = 15.554(2) Å，c = 6.623(6) A。该空间群在纯有机分子中很少见，因为在不对称单元中，乙内酰脲环位于镜面m上。相邻乙内酰脲环之间形成 N-H·O 强氢键类型的分子间相互作用，从而稳定晶体堆积。此外，晶体结构呈现出较弱的C–H···O型非常规氢键的形成。这些氢键形成8、24和36元环型超分子结构，分别由图R ² ₂ (8)、R ⁴ ₄ (24)和R ⁸ ₈ (36)描述，它控制 1,5,5-三甲基-咪唑烷-2,4-二酮的超分子结构的堆积。

晶体结构的 Hirshfeld 表面分析表明，对晶体堆积最重要的贡献来自 H···H (58.3%) 和 H··O/O··H (34.0%) 相互作用，这表明范德华相互作用是晶体堆积中的主导力。能量框架计算表明分子之间形成的接触是轻微静电的。

还通过使用 NCI 方法对电子密度 (ρ) 进行拓扑分析来研究这些分子间相互作用。这种新型乙内酰脲化合物获得的实验和理论结果表明，N-H···O 和 C-H···O 相互作用在其超分子结构的稳定中发挥着重要作用。