Balisetty, LahariCrystallography, in simplest terms, is the study of crystals, their atomic arrangement,symmetry, and morphology. This knowledge is applied across disciplines ranging from determining the structure of geological minerals to biologically important compounds such as deoxyribonucleic acid(DNA) to high-temperature superconductors and quasi-crystals. The work presented in this dissertation involves structure and property studies of iron chalcogenide heterostructures prepared via intercalation. The tetragonal iron chalcogenides, FeCh (Ch = S, Se) studied in this work possess a layer structure made by linking edge-shared tetrahedra with chalcogen atoms at the corners and an iron atom at the center of each tetrahedron. The weak van der Waals forces holding these layers together make introducing intercalants into the interlayer space feasible. Iron chalcogenide heterostructures were prepared by bottom-up solvothermal growth technique and primarily focused on two kinds of intercalants: layered double hydroxides (LDHs) and metal-amine complexes. Both the intercalants are positively charged and can interact with the chalcogenide layer through electrostatic interactions. Along with electrostatics, the intercalants are strong hydrogen bond donors (O-H, N-H, respectively), and can participate in H-bond formation with chalcogenide anions of the host layers. In this work, we provide structural descriptions for two kinds of intercalated iron heterostructures. First is a twisted layer structure of ethylenediamine intercalated FeS. Layered van der Waals materials are susceptible to disorder and can form various stacking polymorphs through translations and twisted structures due to rotations between layers. We study the influence of intercalation of ethylenediamine molecules on such layer-to-layer twist stacking behavior in iron sulfide. The second type is LDH-iron chalcogenide heterolayered materials. They belong to the family of naturally occurring mineral, tochilinite. A new structure model for the heterolayered material is built using prior knowledge of individual components. The structural insights into this material were applied to synthesize new compositions of tochilinite. A synergistic relationship between the host layers and intercalants can lead to superior properties than constituent components or new emergent properties that are not present in the individual bulk compounds, making these compounds interesting.enDissertationChemistry