Conditions for electronic hybridization between transition-metal dichalcogenide monolayers and physisorbed carbon-conjugated molecules

Abstract

Hybridization effects play a crucial role in determining the electronic properties of hybrid inorganic/organic interfaces. To gain insight into these important interactions, we perform a first-principles study based on hybrid density-functional theory including spin-orbit coupling, focusing on eight representative systems formed by two carbon-conjugated molecules-pyrene and perylene-physisorbed on the transition-metal dichalcogenide monolayers (TMDCs) MoS2, MoSe2 WS2, and WSe2. By means of band unfolding techniques, we analyze the band structures of the considered materials, identifying the contributions of the individual constituents as well as the signatures of their hybridization. Based on symmetry and energetic arguments, we derive general conditions for electronic hybridization between conjugated molecules and underlying TMDCs even when the former do not lie planar on the latter, thus providing the key to predict how their mutual arrangement affect their electronic interactions.

Donors, acceptors, and a bit of aromatics: electronic interactions of molecular adsorbates on hBN and MoS2 monolayers

“…[1][2][3][4][5][6][7][8][9] Depending on their density on the substrate and on their physico-chemical characteristics, physisorbed moieties can introduce localized electronic states, [10][11][12] dispersive bands, 7 or a combination thereof. [13][14][15] The electronic structure of the interface results from the level alignment between the organic and inorganic components [16][17][18][19][20] and the hybridization between their electronic wave-functions. 15,[21][22][23][24] As both these effects depend on the intrinsic nature of the building blocks, the need for systematic analyses on the electronic structure of hybrid systems are in high demand.…”

Donors, Acceptors, and a Bit of Aromatics: Electronic Interactions of Molecular Adsorbates on hBN and MoS$_2$ Monolayers

“…[1][2][3][4][5][6][7][8][9] Depending on their density on the substrate and on their physico-chemical characteristics, physisorbed moieties can introduce localized electronic states, [10][11][12] dispersive bands, 7 or a combination thereof. [13][14][15] The electronic structure of the interface results from the level alignment between the organic and inorganic components [16][17][18][19][20] and the hybridization between their electronic wave-functions. 15,[21][22][23][24] As both these effects depend on the intrinsic nature of the building blocks, the need for systematic analyses on the electronic structure of hybrid systems are in high demand.…”

“…[13][14][15] The electronic structure of the interface results from the level alignment between the organic and inorganic components [16][17][18][19][20] and the hybridization between their electronic wave-functions. 15,[21][22][23][24] As both these effects depend on the intrinsic nature of the building blocks, the need for systematic analyses on the electronic structure of hybrid systems are in high demand.…”

“…Furthermore, DFT calculations are able to deliver work functions, level alignments, band structures, and (projected) density of states, among other important properties. 2,[13][14][15]27 While state-of-the-art first-principles methods to obtain the electronic structure of solid-state materials are currently based on many-body perturbation theory, 18,28 the choice of range-separated hybrid functionals to approximate the exchange-correlation potential in DFT offers the optimal trade-off between accuracy and computational costs. 15,27 Proper inclusion of van der Waals interactions improves the prediction of structural arrangements and hence the description of electronic properties.…”

“…2,[13][14][15]27 While state-of-the-art first-principles methods to obtain the electronic structure of solid-state materials are currently based on many-body perturbation theory, 18,28 the choice of range-separated hybrid functionals to approximate the exchange-correlation potential in DFT offers the optimal trade-off between accuracy and computational costs. 15,27 Proper inclusion of van der Waals interactions improves the prediction of structural arrangements and hence the description of electronic properties. 29 The level of accuracy currently achieved by such ab initio calculations ensures reliable results complementary to experiments.…”