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CaW is Zintl Phase structured and crystallizes in the tetragonal I4_1/amd space group. The structure is three-dimensional and consists of two CaW frameworks. Ca is bonded to four equivalent W atoms to form distorted corner-sharing CaW4 tetrahedra. All Ca–W bond lengths are 2.99 Å. W is bonded to four equivalent Ca atoms to form distorted corner-sharing WCa4 tetrahedra.
Nb4C3Si is MAX Phase structured and crystallizes in the hexagonal P6_3/mmc space group. The structure is two-dimensional and consists of two silicon molecules and two Nb4C3 sheets oriented in the (0, 0, 1) direction. In each Nb4C3 sheet, there are two inequivalent Nb2+ sites. In the first Nb2+ site, Nb2+ is bonded to six C4- atoms to form a mixture of edge and corner-sharing NbC6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are three shorter (2.25 Å) and three longer (2.28 Å) Nb–C bond lengths. In the second Nb2+ site, Nb2+ is bonded in a distorted T-shaped geometry to three equivalent C4- atoms. All Nb–C bond lengths are 2.20 Å. There are two inequivalent C4- sites. In the first C4- site, C4- is bonded to six equivalent Nb2+ atoms to form a mixture of edge and corner-sharing CNb6 octahedra. The corner-sharing octahedral tilt angles are 1°. In the second C4- site, C4- is bonded to six Nb2+ atoms to form a mixture of edge and corner-sharing CNb6 octahedra. The corner-sharing octahedral tilt angles are 1°.
Nb4AlN3 is MAX Phase structured and crystallizes in the hexagonal P6_3/mmc space group. The structure is three-dimensional. there are two inequivalent Nb sites. In the first Nb site, Nb is bonded to six N atoms to form a mixture of corner and edge-sharing NbN6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are three shorter (2.19 Å) and three longer (2.25 Å) Nb–N bond lengths. In the second Nb site, Nb is bonded in a 3-coordinate geometry to three equivalent Al and three equivalent N atoms. All Nb–Al bond lengths are 2.85 Å. All Nb–N bond lengths are 2.20 Å. Al is bonded to six equivalent Nb atoms to form distorted AlNb6 cuboctahedra that share corners with six equivalent NNb6 octahedra, edges with six equivalent AlNb6 cuboctahedra, and edges with six equivalent NNb6 octahedra. The corner-sharing octahedral tilt angles are 16°. There are two inequivalent N sites. In the first N site, N is bonded to six equivalent Nb atoms to form a mixture of corner and edge-sharing NNb6 octahedra. The corner-sharing octahedral tilt angles are 2°. In the second N site, N is bonded to six Nb atoms to form NNb6 octahedra that share corners with three equivalent AlNb6 cuboctahedra, corners with three equivalent NNb6 octahedra, edges with three equivalent AlNb6 cuboctahedra, and edges with nine NNb6 octahedra. The corner-sharing octahedral tilt angles are 2°.
Ti4GaC3 is MAX Phase structured and crystallizes in the hexagonal P6_3/mmc space group. The structure is two-dimensional and consists of two gallium molecules and two Ti4C3 sheets oriented in the (0, 0, 1) direction. In each Ti4C3 sheet, there are two inequivalent Ti+2.25+ sites. In the first Ti+2.25+ site, Ti+2.25+ is bonded in a distorted T-shaped geometry to three equivalent C4- atoms. All Ti–C bond lengths are 2.08 Å. In the second Ti+2.25+ site, Ti+2.25+ is bonded to six C4- atoms to form a mixture of edge and corner-sharing TiC6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are three shorter (2.15 Å) and three longer (2.23 Å) Ti–C bond lengths. There are two inequivalent C4- sites. In the first C4- site, C4- is bonded to six equivalent Ti+2.25+ atoms to form a mixture of edge and corner-sharing CTi6 octahedra. The corner-sharing octahedral tilt angles are 3°. In the second C4- site, C4- is bonded to six Ti+2.25+ atoms to form a mixture of edge and corner-sharing CTi6 octahedra. The corner-sharing octahedral tilt angles are 3°.
V4AlN3 is MAX Phase structured and crystallizes in the hexagonal P6_3/mmc space group. The structure is three-dimensional. there are two inequivalent V sites. In the first V site, V is bonded to six N atoms to form a mixture of edge and corner-sharing VN6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are three shorter (2.06 Å) and three longer (2.10 Å) V–N bond lengths. In the second V site, V is bonded in a 3-coordinate geometry to three equivalent Al and three equivalent N atoms. All V–Al bond lengths are 2.79 Å. All V–N bond lengths are 1.96 Å. Al is bonded to six equivalent V and six equivalent Al atoms to form AlAl6V6 cuboctahedra that share corners with six equivalent AlAl6V6 cuboctahedra, corners with six equivalent NV6 octahedra, edges with six equivalent AlAl6V6 cuboctahedra, edges with six equivalent NV6 octahedra, and faces with six equivalent AlAl6V6 cuboctahedra. The corner-sharing octahedral tilt angles are 22°. All Al–Al bond lengths are 2.94 Å. There are two inequivalent N sites. In the first N site, N is bonded to six equivalent V atoms to form a mixture of edge and corner-sharing NV6 octahedra. The corner-sharing octahedral tilt angles are 2°. In the second N site, N is bonded to six V atoms to form NV6 octahedra that share corners with three equivalent AlAl6V6 cuboctahedra, corners with three equivalent NV6 octahedra, edges with three equivalent AlAl6V6 cuboctahedra, and edges with nine NV6 octahedra. The corner-sharing octahedral tilt angles are 2°.
AlCs is Zintl Phase structured and crystallizes in the tetragonal I4_1/amd space group. The structure is three-dimensional and consists of two AlCs frameworks. Cs is bonded to four equivalent Al atoms to form distorted corner-sharing CsAl4 tetrahedra. All Cs–Al bond lengths are 3.62 Å. Al is bonded to four equivalent Cs atoms to form distorted corner-sharing AlCs4 tetrahedra.
Ta4AlN3 is MAX Phase structured and crystallizes in the hexagonal P6_3/mmc space group. The structure is three-dimensional. there are two inequivalent Ta sites. In the first Ta site, Ta is bonded to six N atoms to form a mixture of edge and corner-sharing TaN6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are three shorter (2.18 Å) and three longer (2.23 Å) Ta–N bond lengths. In the second Ta site, Ta is bonded in a 3-coordinate geometry to three equivalent Al and three equivalent N atoms. All Ta–Al bond lengths are 2.83 Å. All Ta–N bond lengths are 2.20 Å. Al is bonded in a 12-coordinate geometry to six equivalent Ta atoms. There are two inequivalent N sites. In the first N site, N is bonded to six equivalent Ta atoms to form a mixture of edge and corner-sharing NTa6 octahedra. The corner-sharing octahedral tilt angles are 2°. In the second N site, N is bonded to six Ta atoms to form a mixture of edge and corner-sharing NTa6 octahedra. The corner-sharing octahedral tilt angles are 2°.
Hadron beams develop intensity-dependent transverse-longitudinal correlations within radio-frequency quadrupole (RFQ) accelerating structures. These correlations are only visible in six-dimensional phase space and are destroyed by reconstructions from low-dimensional projections. In this work, we estimate the effect of artificial decorrelation on the beam dynamics in the Spallation Neutron Source (SNS) linac and Beam Test Facility (BTF). We show that the evolution of a realistic initial distribution and its decorrelated twin converge during the early acceleration stages; thus, low-dimensional projections are probably sufficient for detailed predictions in high-power linacs.
Reduced-complexity climate models (RCMs) are critical in the policy and decision making space, and are directly used within multiple Intergovernmental Panel on Climate Change (IPCC) reports to complement the results of more comprehensive Earth system models. To date, evaluation of RCMs has been limited to a few independent studies. Here we introduce a systematic evaluation of RCMs in the form of the Reduced Complexity Model Intercomparison Project (RCMIP). We expect RCMIP will extend over multiple phases, with Phase 1 being the first. In Phase 1, we focus on the RCMs' global-mean temperature responses, comparing them to observations, exploring the extent to which they emulate more complex models and considering how the relationship between temperature and cumulative emissions of CO2 varies across the RCMs. Our work uses experiments which mirror those found in the Coupled Model Intercomparison Project (CMIP), which focuses on complex Earth system and atmosphere–ocean general circulation models. Using both scenario-based and idealised experiments, we examine RCMs' global-mean temperature response under a range of forcings. We find that the RCMs can all reproduce the approximately 1°C of warming since pre-industrial times, with varying representations of natural variability, volcanic eruptions and aerosols. We also find that RCMs can emulate the global-mean temperature response of CMIP models to within a root-mean-square error of 0.2°C over a range of experiments. Furthermore, we find that, for the Representative Concentration Pathway (RCP) and Shared Socioeconomic Pathway (SSP)-based scenario pairs that share the same IPCC Fifth Assessment Report (AR5)-consistent stratospheric-adjusted radiative forcing, the RCMs indicate higher effective radiative forcings for the SSP-based scenarios and correspondingly higher temperatures when run with the same climate settings. In our idealised setup of RCMs with a climate sensitivity of 3°C, the difference for the ssp585–rcp85 pair by 2100 is around 0.23°C(±0.12°C) due to a difference in effective radiative forcings between the two scenarios. Phase 1 demonstrates the utility of RCMIP's open-source infrastructure, paving the way for further phases of RCMIP to build on the research presented here and deepen our understanding of RCMs.
V2CAs is H-Phase structured and crystallizes in the hexagonal P6_3/mmc space group. The structure is three-dimensional. V+3.50+ is bonded to three equivalent C4- and three equivalent As3- atoms to form a mixture of distorted corner, edge, and face-sharing VAs3C3 octahedra. The corner-sharing octahedra tilt angles range from 0–41°. All V–C bond lengths are 2.08 Å. All V–As bond lengths are 2.55 Å. C4- is bonded to six equivalent V+3.50+ atoms to form edge-sharing CV6 octahedra. As3- is bonded in a 6-coordinate geometry to six equivalent V+3.50+ atoms.
Cr2GaN is H-Phase structured and crystallizes in the hexagonal P6_3/mmc space group. The structure is three-dimensional. Cr is bonded in a 3-coordinate geometry to three equivalent Ga and three equivalent N atoms. All Cr–Ga bond lengths are 2.68 Å. All Cr–N bond lengths are 1.96 Å. Ga is bonded to six equivalent Cr atoms to form distorted GaCr6 cuboctahedra that share corners with six equivalent NCr6 octahedra, edges with six equivalent GaCr6 cuboctahedra, and edges with six equivalent NCr6 octahedra. The corner-sharing octahedral tilt angles are 21°. N is bonded to six equivalent Cr atoms to form NCr6 octahedra that share corners with six equivalent GaCr6 cuboctahedra, edges with six equivalent GaCr6 cuboctahedra, and edges with six equivalent NCr6 octahedra.
CsYbSe2 is H-Phase structured and crystallizes in the hexagonal P6_3/mmc space group. The structure is three-dimensional. Cs1+ is bonded in a 6-coordinate geometry to six equivalent Se2- atoms. All Cs–Se bond lengths are 3.64 Å. Yb3+ is bonded to six equivalent Se2- atoms to form edge-sharing YbSe6 octahedra. All Yb–Se bond lengths are 2.96 Å. Se2- is bonded to three equivalent Cs1+ and three equivalent Yb3+ atoms to form a mixture of distorted edge, face, and corner-sharing SeCs3Yb3 octahedra. The corner-sharing octahedra tilt angles range from 0–41°.
Ti2GaC is H-Phase structured and crystallizes in the hexagonal P6_3/mmc space group. The structure is three-dimensional. Ti is bonded in a 3-coordinate geometry to three equivalent Ga and three equivalent C atoms. All Ti–Ga bond lengths are 2.84 Å. All Ti–C bond lengths are 2.11 Å. Ga is bonded in a 12-coordinate geometry to six equivalent Ti atoms. C is bonded to six equivalent Ti atoms to form edge-sharing CTi6 octahedra.
Ti2AlC is H-Phase structured and crystallizes in the hexagonal P6_3/mmc space group. The structure is three-dimensional. Ti is bonded in a 3-coordinate geometry to three equivalent Al and three equivalent C atoms. All Ti–Al bond lengths are 2.89 Å. All Ti–C bond lengths are 2.11 Å. Al is bonded to six equivalent Ti and six equivalent Al atoms to form distorted AlTi6Al6 cuboctahedra that share corners with six equivalent AlTi6Al6 cuboctahedra, corners with six equivalent CTi6 octahedra, edges with six equivalent AlTi6Al6 cuboctahedra, edges with six equivalent CTi6 octahedra, and faces with six equivalent AlTi6Al6 cuboctahedra. The corner-sharing octahedral tilt angles are 19°. All Al–Al bond lengths are 3.07 Å. C is bonded to six equivalent Ti atoms to form CTi6 octahedra that share corners with six equivalent AlTi6Al6 cuboctahedra, edges with six equivalent AlTi6Al6 cuboctahedra, and edges with six equivalent CTi6 octahedra.
LiGa is Zintl Phase structured and crystallizes in the cubic Fd-3m space group. The structure is three-dimensional and consists of two LiGa frameworks. Li is bonded to four equivalent Ga atoms to form distorted corner-sharing LiGa4 tetrahedra. All Li–Ga bond lengths are 2.71 Å. Ga is bonded to four equivalent Li atoms to form distorted corner-sharing GaLi4 tetrahedra.
Sc2AlC is H-Phase structured and crystallizes in the hexagonal P6_3/mmc space group. The structure is three-dimensional. Sc is bonded in a 3-coordinate geometry to three equivalent Al and three equivalent C atoms. All Sc–Al bond lengths are 3.16 Å. All Sc–C bond lengths are 2.27 Å. Al is bonded in a 6-coordinate geometry to six equivalent Sc atoms. C is bonded to six equivalent Sc atoms to form edge-sharing CSc6 octahedra.
Sc2TlC is H-Phase structured and crystallizes in the hexagonal P6_3/mmc space group. The structure is three-dimensional. Sc is bonded in a 3-coordinate geometry to three equivalent Tl and three equivalent C atoms. All Sc–Tl bond lengths are 3.26 Å. All Sc–C bond lengths are 2.30 Å. Tl is bonded to six equivalent Sc and six equivalent Tl atoms to form distorted TlSc6Tl6 cuboctahedra that share corners with six equivalent TlSc6Tl6 cuboctahedra, corners with six equivalent CSc6 octahedra, edges with six equivalent TlSc6Tl6 cuboctahedra, edges with six equivalent CSc6 octahedra, and faces with six equivalent TlSc6Tl6 cuboctahedra. The corner-sharing octahedral tilt angles are 21°. All Tl–Tl bond lengths are 3.38 Å. C is bonded to six equivalent Sc atoms to form CSc6 octahedra that share corners with six equivalent TlSc6Tl6 cuboctahedra, edges with six equivalent TlSc6Tl6 cuboctahedra, and edges with six equivalent CSc6 octahedra.
Hf2SC is H-Phase structured and crystallizes in the hexagonal P6_3/mmc space group. The structure is three-dimensional. Hf is bonded to three equivalent C and three equivalent S atoms to form a mixture of edge, face, and corner-sharing HfC3S3 octahedra. The corner-sharing octahedra tilt angles range from 0–43°. All Hf–C bond lengths are 2.29 Å. All Hf–S bond lengths are 2.66 Å. C is bonded to six equivalent Hf atoms to form CHf6 octahedra that share corners with six equivalent SHf6 pentagonal pyramids, edges with six equivalent CHf6 octahedra, and edges with six equivalent SHf6 pentagonal pyramids. S is bonded to six equivalent Hf atoms to form distorted SHf6 pentagonal pyramids that share corners with six equivalent CHf6 octahedra, edges with six equivalent CHf6 octahedra, and edges with six equivalent SHf6 pentagonal pyramids. The corner-sharing octahedral tilt angles are 11°.