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At least 19 records
All sourcesNASA NTRSDOE OSTI
DOE OSTI2020

Materials Data on Te2Mo(WS2)2 by Materials Project

MoTe2(WS2)2 is Molybdenite-derived structured and crystallizes in the hexagonal P-6m2 space group. The structure is two-dimensional and consists of one MoTe2 sheet oriented in the (0, 0, 1) direction and two WS2 sheets oriented in the (0, 0, 1) direction. In the MoTe2 sheet, Mo6+ is bonded to six equivalent Te2- atoms to form distorted edge-sharing MoTe6 pentagonal pyramids. All Mo–Te bond lengths are 2.70 Å. Te2- is bonded to three equivalent Mo6+ atoms to form a mixture of distorted face and corner-sharing TeMo3 cuboctahedra. In each WS2 sheet, W3+ is bonded to six S2- atoms to form distorted edge-sharing WS6 pentagonal pyramids. All W–S bond lengths are 2.45 Å. There are two inequivalent S2- sites. In the first S2- site, S2- is bonded in a distorted T-shaped geometry to three equivalent W3+ atoms. In the second S2- site, S2- is bonded in a 3-coordinate geometry to three equivalent W3+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Te2Mo(WS2)2 by Materials Project

MoTe2(WS2)2 is Molybdenite-derived structured and crystallizes in the trigonal P3m1 space group. The structure is two-dimensional and consists of one MoTe2 sheet oriented in the (0, 0, 1) direction and two WS2 sheets oriented in the (0, 0, 1) direction. In the MoTe2 sheet, Mo6+ is bonded to six Te2- atoms to form distorted edge-sharing MoTe6 pentagonal pyramids. All Mo–Te bond lengths are 2.70 Å. There are two inequivalent Te2- sites. In the first Te2- site, Te2- is bonded in a 3-coordinate geometry to three equivalent Mo6+ atoms. In the second Te2- site, Te2- is bonded to three equivalent Mo6+ atoms to form distorted corner-sharing TeMo3 cuboctahedra. In each WS2 sheet, W3+ is bonded to six S2- atoms to form distorted edge-sharing WS6 pentagonal pyramids. All W–S bond lengths are 2.45 Å. There are two inequivalent S2- sites. In the first S2- site, S2- is bonded in a 3-coordinate geometry to three equivalent W3+ atoms. In the second S2- site, S2- is bonded in a distorted T-shaped geometry to three equivalent W3+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Te2Mo(WS2)3 by Materials Project

WTe2(WS2)2MoS2 is Molybdenite-derived structured and crystallizes in the trigonal P3m1 space group. The structure is two-dimensional and consists of one MoS2 sheet oriented in the (0, 0, 1) direction; two WS2 sheets oriented in the (0, 0, 1) direction; and one WTe2 sheet oriented in the (0, 0, 1) direction. In the MoS2 sheet, Mo6+ is bonded to six S2- atoms to form distorted edge-sharing MoS6 pentagonal pyramids. All Mo–S bond lengths are 2.44 Å. There are two inequivalent S2- sites. In the first S2- site, S2- is bonded in a 3-coordinate geometry to three equivalent Mo6+ atoms. In the second S2- site, S2- is bonded in a distorted T-shaped geometry to three equivalent Mo6+ atoms. In each WS2 sheet, W+3.33+ is bonded to six equivalent S2- atoms to form distorted edge-sharing WS6 pentagonal pyramids. All W–S bond lengths are 2.44 Å. S2- is bonded in a 3-coordinate geometry to three equivalent W+3.33+ atoms. In the WTe2 sheet, W+3.33+ is bonded in a 6-coordinate geometry to six Te2- atoms. All W–Te bond lengths are 2.71 Å. There are two inequivalent Te2- sites. In the first Te2- site, Te2- is bonded in a 3-coordinate geometry to three equivalent W+3.33+ atoms. In the second Te2- site, Te2- is bonded in a 12-coordinate geometry to three equivalent W+3.33+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Te2Mo(WS2)3 by Materials Project

WTe2(WS2)2MoS2 is Molybdenite-derived structured and crystallizes in the trigonal P3m1 space group. The structure is two-dimensional and consists of one MoS2 sheet oriented in the (0, 0, 1) direction; two WS2 sheets oriented in the (0, 0, 1) direction; and one WTe2 sheet oriented in the (0, 0, 1) direction. In the MoS2 sheet, Mo6+ is bonded to six equivalent S2- atoms to form distorted edge-sharing MoS6 pentagonal pyramids. All Mo–S bond lengths are 2.44 Å. S2- is bonded in a 3-coordinate geometry to three equivalent Mo6+ atoms. In each WS2 sheet, W+3.33+ is bonded to six equivalent S2- atoms to form distorted edge-sharing WS6 pentagonal pyramids. All W–S bond lengths are 2.44 Å. S2- is bonded in a 3-coordinate geometry to three equivalent W+3.33+ atoms. In the WTe2 sheet, W+3.33+ is bonded in a 6-coordinate geometry to six Te2- atoms. All W–Te bond lengths are 2.71 Å. There are two inequivalent Te2- sites. In the first Te2- site, Te2- is bonded in a 3-coordinate geometry to three equivalent W+3.33+ atoms. In the second Te2- site, Te2- is bonded in a 12-coordinate geometry to three equivalent W+3.33+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Te2Mo(WS2)3 by Materials Project

MoTe2(WS2)3 is Molybdenite-derived structured and crystallizes in the trigonal P3m1 space group. The structure is two-dimensional and consists of one MoTe2 sheet oriented in the (0, 0, 1) direction and three WS2 sheets oriented in the (0, 0, 1) direction. In the MoTe2 sheet, Mo6+ is bonded in a 6-coordinate geometry to six equivalent Te2- atoms. All Mo–Te bond lengths are 2.70 Å. Te2- is bonded to three equivalent Mo6+ atoms to form a mixture of distorted face and corner-sharing TeMo3 cuboctahedra. In each WS2 sheet, W+3.33+ is bonded to six equivalent S2- atoms to form distorted edge-sharing WS6 pentagonal pyramids. All W–S bond lengths are 2.44 Å. S2- is bonded in a 3-coordinate geometry to three equivalent W+3.33+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Te2Mo(WS2)3 by Materials Project

MoTe2(WS2)3 is Molybdenite-derived structured and crystallizes in the trigonal P3m1 space group. The structure is two-dimensional and consists of one MoTe2 sheet oriented in the (0, 0, 1) direction and three WS2 sheets oriented in the (0, 0, 1) direction. In the MoTe2 sheet, Mo6+ is bonded in a 6-coordinate geometry to six Te2- atoms. All Mo–Te bond lengths are 2.70 Å. There are two inequivalent Te2- sites. In the first Te2- site, Te2- is bonded in a 3-coordinate geometry to three equivalent Mo6+ atoms. In the second Te2- site, Te2- is bonded to three equivalent Mo6+ atoms to form distorted corner-sharing TeMo3 cuboctahedra. In each WS2 sheet, W+3.33+ is bonded to six equivalent S2- atoms to form distorted edge-sharing WS6 pentagonal pyramids. All W–S bond lengths are 2.44 Å. S2- is bonded in a 3-coordinate geometry to three equivalent W+3.33+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Te2Mo(WS2)3 by Materials Project

WTe2(WS2)2MoS2 is Molybdenite-derived structured and crystallizes in the trigonal P3m1 space group. The structure is two-dimensional and consists of one MoS2 sheet oriented in the (0, 0, 1) direction; two WS2 sheets oriented in the (0, 0, 1) direction; and one WTe2 sheet oriented in the (0, 0, 1) direction. In the MoS2 sheet, Mo6+ is bonded to six equivalent S2- atoms to form distorted edge-sharing MoS6 pentagonal pyramids. All Mo–S bond lengths are 2.44 Å. S2- is bonded in a 3-coordinate geometry to three equivalent Mo6+ atoms. In each WS2 sheet, W+3.33+ is bonded to six equivalent S2- atoms to form distorted edge-sharing WS6 pentagonal pyramids. All W–S bond lengths are 2.44 Å. S2- is bonded in a 3-coordinate geometry to three equivalent W+3.33+ atoms. In the WTe2 sheet, W+3.33+ is bonded in a 6-coordinate geometry to six Te2- atoms. All W–Te bond lengths are 2.71 Å. There are two inequivalent Te2- sites. In the first Te2- site, Te2- is bonded in a 3-coordinate geometry to three equivalent W+3.33+ atoms. In the second Te2- site, Te2- is bonded in a 12-coordinate geometry to three equivalent W+3.33+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2021

Direct observation of negative differential resistance in WS2 homojunction

Vertical tunneling junctions showing negative differential resistance (NDR) are realized in WS2 homojunction devices. Mono-/multilayered single crystalline WS2 is grown using chemical vapor deposition. NDR is observed through resonant tunneling in Au/bi-layer WS2/Au and Pt/few-layered WS2/Au tunneling junctions by back-gating at room temperature. While two-dimensional materials have been a central focus of materials research during the past decade, exploiting novel properties in diverse layers of these materials is emerging with new designs for electronic devices. Our results pave the way for novel resonant tunneling devices presenting a route to fabricate homojunction WS2 with simple fabrication techniques.

Hsu, Bo (ORCID:0000000201714211)↗
DOE OSTI2020

Materials Data on WS2 by Materials Project

WS2 is Molybdenite structured and crystallizes in the hexagonal P6_3/mmc space group. The structure is two-dimensional and consists of two WS2 sheets oriented in the (0, 0, 1) direction. W4+ is bonded to six equivalent S2- atoms to form distorted edge-sharing WS6 pentagonal pyramids. All W–S bond lengths are 2.42 Å. S2- is bonded in a 3-coordinate geometry to three equivalent W4+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on WS2 by Materials Project

WS2 is Molybdenite-like structured and crystallizes in the trigonal R3m space group. The structure is two-dimensional and consists of three WS2 sheets oriented in the (0, 0, 1) direction. W4+ is bonded to six equivalent S2- atoms to form distorted edge-sharing WS6 pentagonal pyramids. All W–S bond lengths are 2.42 Å. S2- is bonded in a 3-coordinate geometry to three equivalent W4+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on WS2 by Materials Project

WS2 is Molybdenite-like structured and crystallizes in the hexagonal P-6m2 space group. The structure is two-dimensional and consists of one WS2 sheet oriented in the (0, 0, 1) direction. W4+ is bonded to six equivalent S2- atoms to form distorted edge-sharing WS6 pentagonal pyramids. All W–S bond lengths are 2.42 Å. S2- is bonded in a 3-coordinate geometry to three equivalent W4+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on WS2 by Materials Project

WS2 is Molybdenite-like structured and crystallizes in the trigonal P-3m1 space group. The structure is two-dimensional and consists of two WS2 sheets oriented in the (0, 0, 1) direction. W4+ is bonded to six equivalent S2- atoms to form distorted edge-sharing WS6 pentagonal pyramids. All W–S bond lengths are 2.42 Å. S2- is bonded in a 3-coordinate geometry to three equivalent W4+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Te2Mo(WS2)2 by Materials Project

WTe2WS2MoS2 is Molybdenite-derived structured and crystallizes in the trigonal P3m1 space group. The structure is two-dimensional and consists of one MoS2 sheet oriented in the (0, 0, 1) direction; one WS2 sheet oriented in the (0, 0, 1) direction; and one WTe2 sheet oriented in the (0, 0, 1) direction. In the MoS2 sheet, Mo6+ is bonded to six S2- atoms to form distorted edge-sharing MoS6 pentagonal pyramids. All Mo–S bond lengths are 2.44 Å. There are two inequivalent S2- sites. In the first S2- site, S2- is bonded in a distorted T-shaped geometry to three equivalent Mo6+ atoms. In the second S2- site, S2- is bonded in a 3-coordinate geometry to three equivalent Mo6+ atoms. In the WS2 sheet, W3+ is bonded to six equivalent S2- atoms to form distorted edge-sharing WS6 pentagonal pyramids. All W–S bond lengths are 2.45 Å. S2- is bonded in a 3-coordinate geometry to three equivalent W3+ atoms. In the WTe2 sheet, W3+ is bonded to six Te2- atoms to form distorted edge-sharing WTe6 pentagonal pyramids. All W–Te bond lengths are 2.71 Å. There are two inequivalent Te2- sites. In the first Te2- site, Te2- is bonded in a 12-coordinate geometry to three equivalent W3+ atoms. In the second Te2- site, Te2- is bonded in a 3-coordinate geometry to three equivalent W3+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on WS2 by Materials Project

WS2 is Molybdenite-like structured and crystallizes in the hexagonal P-6m2 space group. The structure is two-dimensional and consists of three WS2 sheets oriented in the (0, 0, 1) direction. W4+ is bonded to six equivalent S2- atoms to form distorted edge-sharing WS6 pentagonal pyramids. All W–S bond lengths are 2.42 Å. S2- is bonded in a 3-coordinate geometry to three equivalent W4+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Te2Mo(WS2)2 by Materials Project

WTe2WS2MoS2 is Molybdenite-derived structured and crystallizes in the trigonal P3m1 space group. The structure is two-dimensional and consists of one MoS2 sheet oriented in the (0, 0, 1) direction; one WS2 sheet oriented in the (0, 0, 1) direction; and one WTe2 sheet oriented in the (0, 0, 1) direction. In the MoS2 sheet, Mo6+ is bonded to six S2- atoms to form distorted edge-sharing MoS6 pentagonal pyramids. There are three shorter (2.44 Å) and three longer (2.45 Å) Mo–S bond lengths. There are two inequivalent S2- sites. In the first S2- site, S2- is bonded in a distorted T-shaped geometry to three equivalent Mo6+ atoms. In the second S2- site, S2- is bonded in a 3-coordinate geometry to three equivalent Mo6+ atoms. In the WS2 sheet, W3+ is bonded to six S2- atoms to form distorted edge-sharing WS6 pentagonal pyramids. All W–S bond lengths are 2.45 Å. There are two inequivalent S2- sites. In the first S2- site, S2- is bonded in a distorted T-shaped geometry to three equivalent W3+ atoms. In the second S2- site, S2- is bonded in a 3-coordinate geometry to three equivalent W3+ atoms. In the WTe2 sheet, W3+ is bonded to six equivalent Te2- atoms to form distorted edge-sharing WTe6 pentagonal pyramids. All W–Te bond lengths are 2.71 Å. Te2- is bonded in a 12-coordinate geometry to three equivalent W3+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Te2Mo(WS2)2 by Materials Project

WTe2WS2MoS2 is Molybdenite-derived structured and crystallizes in the trigonal P3m1 space group. The structure is two-dimensional and consists of one MoS2 sheet oriented in the (0, 0, 1) direction; one WS2 sheet oriented in the (0, 0, 1) direction; and one WTe2 sheet oriented in the (0, 0, 1) direction. In the MoS2 sheet, Mo6+ is bonded to six equivalent S2- atoms to form distorted edge-sharing MoS6 pentagonal pyramids. All Mo–S bond lengths are 2.44 Å. S2- is bonded in a 3-coordinate geometry to three equivalent Mo6+ atoms. In the WS2 sheet, W3+ is bonded to six S2- atoms to form distorted edge-sharing WS6 pentagonal pyramids. All W–S bond lengths are 2.45 Å. There are two inequivalent S2- sites. In the first S2- site, S2- is bonded in a distorted T-shaped geometry to three equivalent W3+ atoms. In the second S2- site, S2- is bonded in a 3-coordinate geometry to three equivalent W3+ atoms. In the WTe2 sheet, W3+ is bonded to six Te2- atoms to form distorted edge-sharing WTe6 pentagonal pyramids. All W–Te bond lengths are 2.71 Å. There are two inequivalent Te2- sites. In the first Te2- site, Te2- is bonded in a 12-coordinate geometry to three equivalent W3+ atoms. In the second Te2- site, Te2- is bonded in a 3-coordinate geometry to three equivalent W3+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on WS2 by Materials Project

WS2 is Molybdenite-like structured and crystallizes in the trigonal P-3m1 space group. The structure is two-dimensional and consists of four WS2 sheets oriented in the (0, 0, 1) direction. W4+ is bonded to six equivalent S2- atoms to form distorted edge-sharing WS6 pentagonal pyramids. All W–S bond lengths are 2.42 Å. S2- is bonded in a 3-coordinate geometry to three equivalent W4+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2025

Graphene-driven correlated electronic states in one dimensional defects within WS2

Tomonaga-Luttinger liquid (TLL) behavior in one-dimensional systems has been predicted and shown to occur at semiconductor-to-metal transitions within two-dimensional materials. Reports of one-dimensional defects hosting a Fermi liquid or a TLL have suggested a dependence on the underlying substrate, however, unveiling the physical details of electronic contributions from the substrate require cross-correlative investigation. Here, we study TLL formation within defectively engineered WS2 atop graphene, where band structure and the atomic environment is visualized with nano angle-resolved photoelectron spectroscopy, scanning tunneling microscopy and spectroscopy, and non-contact atomic force microscopy. Correlations between the local density of states and electronic band dispersion elucidated the electron transfer from graphene into a TLL hosted by one-dimensional metal (1DM) defects. It appears that the vertical heterostructure with graphene and the induced charge transfer from graphene into the 1DM is critical for the formation of a TLL.

Rossi, Antonio↗