이 연구에서는 불화암모늄이 도핑된 구조 II (clathrate structure II) 하이드레이트 내에 에폭시사이클로펜탄(ECP)과

메탄올(MeOH)이 포집된 결정 구조를 정밀 분석하였다. 하이드레이트의 주체 격자는 불화암모늄과 물 분자로 구성되

며, ECP 및 메탄올은 객체 분자로서 각각 큰 동공과 작은 동공 내에 포집될 가능성이 검토되었다. 분말 X-선 회절

(PXRD) 및 Rietveld 정련법을 통해 구조 II 하이드레이트의 형성을 확인하였으며, direct space method를 활용하여 동

공 내 객체 분자의 위치를 정밀하게 모델링하였다. 시각화 및 분자 간 거리 분석 결과, ECP는 큰 동공 내에, 메탄올은

작은 동공에 안정적으로 포집되었으며, 수소결합 가능성을 지닌 상호작용이 관찰되었다. 이러한 결과는 억제제 계열

분자의 포집 메커니즘에 대한 기초 데이터를 제고해줄 것으로 여겨진다.

In this study, the crystal structure of clathrate structure II hydrate doped with ammonium fluoride was

thoroughly analyzed with a focus on the encapsulation of epoxybicyclopentane (ECP) and methanol (MeOH). The host

lattice of the hydrate is composed of ammonium fluoride and water molecules, while ECP and MeOH act as guest

molecules occupying the large and small cages, respectively. Powder X-ray diffraction (PXRD) combined with Rietveld

refinement confirmed the formation of structure II hydrate. The positions of the guest molecules in the cages were

accurately modeled using a direct space method. Visualization and intermolecular distance analysis revealed that ECP is

stably encapsulated in the large cages, while MeOH is stabilized in the small cages through interactions that potentially

involve hydrogen bonding. These findings provide fundamental insights into the encapsulation mechanism of inhibitortype

guest molecules.

Clathrtae hydrate, Epoxycyclopentane, Ammonium fluoride, Methanol, Structural analysis

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