Novel thioureas RNHC­(S)­NHP­(S)­(OiPr)2 [R = (HOCH2)­(Me)2C (1), Me2CH2CH2 (2), 2-CF3C6H4 (3), 2-Pym (4), and bis-thiourea 1,5-C10H6{NHC­(S)­NHP­(S)­(OiPr)2} (5)] have been synthesized and characterized by NMR, X-ray diffraction, Hirshfeld surface analysis, and theoretical ETS-NOCV charge and energy decomposition calculations. The monomers contain multiple intramolecular noncovalent interactions including N–H···X (X = O, 1–3; F, 3; N, 4; S, 5) and C–H···Y (Y = O, 1; N, 2 and 3; S, 4 and 5) augmented further by homopolar C–H···H–C contacts in all the structures. It has been determined that the three-dimensional crystal networks are primarily constituted from intermolecular H···H and H···S contacts due to homopolar C–H···H–C as well as X–H···S (X = N, C) interactions. They are, depending on the system, augmented further by C–H···Y (Y = π, S, F) as well as by σ-hole­(S)···π interactions. ETS-NOCV allowed us to delineate that in the case of C–H···H–C, C–H···Y, and σ-hole­(S)···π intermolecular interactions, except for the electrostatically dominated N–H···N in 4, London dispersion forces appeared to be a crucial contributor to the stability with non-negligible factors stemming from electrostatics and charge delocalization terms. Remarkably, the dispersion dominated (∼50% of the overall stabilization ΔE elstat + ΔE orb + ΔE dispersion) σ-hole­(S)···π interactions appeared to be the strongest among all the discovered interactions, including classical hydrogen bonds N–H···N. The electrostatic and charge delocalization contributions within the σ-hole­(S)···π interactions amount to ∼30% and ∼20%, respectively.

A family of thiourea based derivatives, RNHC(S)NHP(S)(OiPr)2 [R = Ph (YEZNUN), 2‐MeC6H4 (AQOYAH), 2,5‐Me2C6H3 (WARREO), 2,6‐Me2C6H3 (GUJGUO), 2,4,6‐Me3C6H2 (AQOYEL), PhNH (QORXUR), 1‐naphthyl (MOWPEU)], has been studied to understand the synergy between dihydrogen and other (non)conventional non‐covalent interactions. It was established that all monomers are stabilized through intramolecular dihydrogen C–H···H–C interactions. Additionally, C–H···π interactions are noted in AQOYAH, WARREO, and MOWPEU; N–H···O interactions in AQOYAH, and WARREO; C–H···S interactions in GUJGUO, YEZNUN, and AQOYEL; N–H···S interactions in GUJGUO, AQOYEL, MOWPEU, and YEZNUN; and N–H···N interactions in QORXUR. The crystal structures of all the thioureas are further stabilized by the most pronounced intermolecular C–H···H–C interactions followed by N–H···S and C–H···S with the formation of centrosymmetric R22(8) dimers. These non‐covalent interactions are augmented by the π···π stacking in YEZNUN and MOWPEU; C–H···π in WARREO, GUJGUO, AQOYEL and MOWPEU; N–H···π in QORXUR. The synergy between intra‐ and intermolecular C–H···H–C and other types of non‐covalent interactions lead to the extraordinary stability of these systems as indicated by the ETS‐NOCV Scheme Although the London dispersion forces cover ≈ 70–80 % of the overall C–H···H–C stabilization, the covalent‐like charge delocalization based on depletion of electron charge from the σ(C–H) orbitals to the inter‐atomic H···H region contributes notably up to 15 %.

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