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At least 451 records · Page 25

Materials Data on TlRh3 by Materials Project

Rh3Tl is beta Cu3Ti-like structured and crystallizes in the hexagonal P6_3/mmc space group. The structure is three-dimensional. there are two inequivalent Rh sites. In the first Rh site, Rh is bonded to eight Rh and four equivalent Tl atoms to form distorted RhTl4Rh8 cuboctahedra that share corners with four equivalent TlRh12 cuboctahedra, corners with fourteen RhTl4Rh8 cuboctahedra, edges with six equivalent TlRh12 cuboctahedra, edges with twelve RhTl4Rh8 cuboctahedra, faces with four equivalent TlRh12 cuboctahedra, and faces with sixteen RhTl4Rh8 cuboctahedra. There are a spread of Rh–Rh bond distances ranging from 2.75–2.96 Å. There are two shorter (2.85 Å) and two longer (2.86 Å) Rh–Tl bond lengths. In the second Rh site, Rh is bonded to eight equivalent Rh and four equivalent Tl atoms to form distorted RhTl4Rh8 cuboctahedra that share corners with four equivalent TlRh12 cuboctahedra, corners with fourteen RhTl4Rh8 cuboctahedra, edges with six equivalent TlRh12 cuboctahedra, edges with twelve equivalent RhTl4Rh8 cuboctahedra, faces with four equivalent TlRh12 cuboctahedra, and faces with sixteen RhTl4Rh8 cuboctahedra. There are two shorter (2.85 Å) and two longer (2.86 Å) Rh–Tl bond lengths. Tl is bonded to twelve Rh atoms to form TlRh12 cuboctahedra that share corners with six equivalent TlRh12 cuboctahedra, corners with twelve equivalent RhTl4Rh8 cuboctahedra, edges with eighteen RhTl4Rh8 cuboctahedra, faces with eight equivalent TlRh12 cuboctahedra, and faces with twelve RhTl4Rh8 cuboctahedra.

36 MATERIALS SCIENCE↗

Materials Data on Er2Si5Rh3 by Materials Project

Er2Rh3Si5 crystallizes in the orthorhombic Ibam space group. The structure is three-dimensional. Er is bonded in a 1-coordinate geometry to seven Rh and ten Si atoms. There are a spread of Er–Rh bond distances ranging from 3.07–3.40 Å. There are a spread of Er–Si bond distances ranging from 2.96–3.20 Å. There are two inequivalent Rh sites. In the first Rh site, Rh is bonded in a 6-coordinate geometry to four equivalent Er and six Si atoms. There are four shorter (2.44 Å) and two longer (2.58 Å) Rh–Si bond lengths. In the second Rh site, Rh is bonded in a 5-coordinate geometry to five equivalent Er and five Si atoms. There are a spread of Rh–Si bond distances ranging from 2.34–2.42 Å. There are three inequivalent Si sites. In the first Si site, Si is bonded in a 3-coordinate geometry to four equivalent Er, three Rh, and two equivalent Si atoms. Both Si–Si bond lengths are 2.51 Å. In the second Si site, Si is bonded in a 9-coordinate geometry to four equivalent Er, three Rh, and two equivalent Si atoms. In the third Si site, Si is bonded in a 4-coordinate geometry to four equivalent Er and four equivalent Rh atoms.

36 MATERIALS SCIENCE↗

Materials Data on Nd2Si5Rh3 by Materials Project

Nd2Rh3Si5 crystallizes in the orthorhombic Ibam space group. The structure is three-dimensional. Nd is bonded in a 1-coordinate geometry to seven Rh and ten Si atoms. There are a spread of Nd–Rh bond distances ranging from 3.13–3.43 Å. There are a spread of Nd–Si bond distances ranging from 3.02–3.24 Å. There are two inequivalent Rh sites. In the first Rh site, Rh is bonded in a 6-coordinate geometry to four equivalent Nd and six Si atoms. There are four shorter (2.46 Å) and two longer (2.65 Å) Rh–Si bond lengths. In the second Rh site, Rh is bonded in a 5-coordinate geometry to five equivalent Nd and five Si atoms. There are a spread of Rh–Si bond distances ranging from 2.40–2.45 Å. There are three inequivalent Si sites. In the first Si site, Si is bonded in a 2-coordinate geometry to four equivalent Nd, three Rh, and two equivalent Si atoms. Both Si–Si bond lengths are 2.54 Å. In the second Si site, Si is bonded in a 9-coordinate geometry to four equivalent Nd, three Rh, and two equivalent Si atoms. In the third Si site, Si is bonded in a 4-coordinate geometry to four equivalent Nd and four equivalent Rh atoms.

36 MATERIALS SCIENCE↗

A theoretical index for understanding distinct land relative humidity trends in observations, reanalyses, and models

Land surface relative humidity (RH) is a key variable in the coupled land–atmosphere system that profoundly influences terrestrial hydroclimate and ecosystems. Yet historical changes in land RH are not well understood due to limited observations, biased reanalyses, and the lack of a framework for interpreting RH changes under multiple influencing factors. Here, we show that the spatiotemporal variability of land RH and its distinct historical trends among observations, reanalyses, and Earth system models are captured by a simple index based on the ratio of precipitation (P) to a modified potential evapotranspiration formulated independently of RH (PET°). The index provides a physical calibration of biased land RH in reanalyses and a quantitative framework for interpreting land RH changes. Over 1973–2024, land RH has decreased substantially, owing to the intrinsic rise in PET° with temperature and little increase in land precipitation. Reanalyses overestimate the observed RH decrease, consistent with exaggerated surface warming and precipitation decline. The index captures this coherent bias and enables a calibration using observed precipitation and temperature. Models simulate a wide range of land RH trends, but nearly all runs underrepresent the historical drying. The index captures the model spread and discrepancy and attributes them to contributions of precipitation and PET°. Weaker land RH decreases in models arise mainly from weaker subtropical precipitation declines, linked to muted intensification of subtropical highs and biased subtropical climatology. The model–observation discrepancy is unlikely explained by internal variability, implying model underestimation of forced RH decrease and a drier land future than current projections.

Earth system models↗

A global model–measurement evaluation of particle light scattering coefficients at elevated relative humidity

The uptake of water by atmospheric aerosols has a pronounced effect on particle light scattering properties, which in turn are strongly dependent on the ambient relative humidity (RH). Earth system models need to account for the aerosol water uptake and its influence on light scattering in order to properly capture the overall radiative effects of aerosols. Here we present a comprehensive model–measurement evaluation of the particle light scattering enhancement factor f(RH), defined as the particle light scattering coefficient at elevated RH (here set to 85 %) divided by its dry value. The comparison uses simulations from 10 Earth system models and a global dataset of surface-based in situ measurements. In general, we find a large diversity in the magnitude of predicted f(RH) amongst the different models, which can not be explained by the site types. Based on our evaluation of sea salt scattering enhancement and simulated organic mass fraction, there is a strong indication that differences in the model parameterizations of hygroscopicity and model chemistry are driving at least some of the observed diversity in simulated f(RH). Additionally, a key point is that defining dry conditions is difficult from an observational point of view and, depending on the aerosol, may influence the measured f(RH). The definition of dry also impacts our model evaluation, because several models exhibit significant water uptake between RH = 0 % and 40 %. The multisite average ratio between model outputs and measurements is 1.64 when RH = 0 % is assumed as the model dry RH and 1.16 when RH = 40 % is the model dry RH value. The overestimation by the models is believed to originate from the hygroscopicity parameterizations at the lower RH range which may not implement all phenomena taking place (i.e., not fully dried particles and hysteresis effects). This will be particularly relevant when a location is dominated by a deliquescent aerosol such as sea salt. Our results emphasize the need to consider the measurement conditions in such comparisons and recognize that measurements referred to as dry may not be dry in model terms. Recommendations for future model–measurement evaluation and model improvements are provided.

54 ENVIRONMENTAL SCIENCES↗

Materials Data on Mg(P2Rh3)2 by Materials Project

Mg(Rh3P2)2 crystallizes in the hexagonal P-6m2 space group. The structure is three-dimensional. Mg is bonded to six equivalent Rh and six equivalent P atoms to form face-sharing MgP6Rh6 cuboctahedra. All Mg–Rh bond lengths are 2.95 Å. All Mg–P bond lengths are 2.91 Å. There are two inequivalent Rh sites. In the first Rh site, Rh is bonded in a 6-coordinate geometry to two equivalent Mg and four P atoms. There are two shorter (2.33 Å) and two longer (2.49 Å) Rh–P bond lengths. In the second Rh site, Rh is bonded in a 5-coordinate geometry to five P atoms. There are four shorter (2.47 Å) and one longer (2.48 Å) Rh–P bond lengths. There are two inequivalent P sites. In the first P site, P is bonded in a 8-coordinate geometry to two equivalent Mg and six Rh atoms. In the second P site, P is bonded in a 9-coordinate geometry to nine Rh atoms.

36 MATERIALS SCIENCE↗

Materials Data on Mg(As2Rh3)2 by Materials Project

Mg(Rh3As2)2 crystallizes in the hexagonal P-6m2 space group. The structure is three-dimensional. Mg is bonded to six equivalent Rh and six equivalent As atoms to form face-sharing MgAs6Rh6 cuboctahedra. All Mg–Rh bond lengths are 3.06 Å. All Mg–As bond lengths are 3.02 Å. There are two inequivalent Rh sites. In the first Rh site, Rh is bonded in a 6-coordinate geometry to two equivalent Mg and four As atoms. There are two shorter (2.43 Å) and two longer (2.56 Å) Rh–As bond lengths. In the second Rh site, Rh is bonded in a 5-coordinate geometry to five As atoms. There are four shorter (2.55 Å) and one longer (2.57 Å) Rh–As bond lengths. There are two inequivalent As sites. In the first As site, As is bonded in a 8-coordinate geometry to two equivalent Mg and six Rh atoms. In the second As site, As is bonded in a 9-coordinate geometry to nine Rh atoms.

36 MATERIALS SCIENCE↗

Materials Data on Ca(As2Rh3)2 by Materials Project

Ca(Rh3As2)2 crystallizes in the hexagonal P-6m2 space group. The structure is three-dimensional. Ca is bonded to six equivalent Rh and six equivalent As atoms to form face-sharing CaAs6Rh6 cuboctahedra. All Ca–Rh bond lengths are 3.16 Å. All Ca–As bond lengths are 3.06 Å. There are two inequivalent Rh sites. In the first Rh site, Rh is bonded in a 6-coordinate geometry to two equivalent Ca and four As atoms. There are two shorter (2.46 Å) and two longer (2.55 Å) Rh–As bond lengths. In the second Rh site, Rh is bonded in a 5-coordinate geometry to five As atoms. There are one shorter (2.55 Å) and four longer (2.59 Å) Rh–As bond lengths. There are two inequivalent As sites. In the first As site, As is bonded in a 8-coordinate geometry to two equivalent Ca and six Rh atoms. In the second As site, As is bonded in a 9-coordinate geometry to nine Rh atoms.

36 MATERIALS SCIENCE↗

Materials Data on Sr(As2Rh3)2 by Materials Project

Sr(Rh3As2)2 crystallizes in the hexagonal P-6m2 space group. The structure is three-dimensional. Sr is bonded to six equivalent Rh and six equivalent As atoms to form face-sharing SrAs6Rh6 cuboctahedra. All Sr–Rh bond lengths are 3.21 Å. All Sr–As bond lengths are 3.10 Å. There are two inequivalent Rh sites. In the first Rh site, Rh is bonded in a 6-coordinate geometry to two equivalent Sr and four As atoms. There are two shorter (2.49 Å) and two longer (2.56 Å) Rh–As bond lengths. In the second Rh site, Rh is bonded in a 5-coordinate geometry to five As atoms. There are one shorter (2.55 Å) and four longer (2.60 Å) Rh–As bond lengths. There are two inequivalent As sites. In the first As site, As is bonded in a 8-coordinate geometry to two equivalent Sr and six Rh atoms. In the second As site, As is bonded in a 9-coordinate geometry to nine Rh atoms.

36 MATERIALS SCIENCE↗

Materials Data on Hf3Rh5 by Materials Project

Hf3Rh5 crystallizes in the orthorhombic Pbam space group. The structure is three-dimensional. there are two inequivalent Hf sites. In the first Hf site, Hf is bonded in a 10-coordinate geometry to ten Rh atoms. There are a spread of Hf–Rh bond distances ranging from 2.69–2.99 Å. In the second Hf site, Hf is bonded in a body-centered cubic geometry to eight Rh atoms. There are a spread of Hf–Rh bond distances ranging from 2.66–2.81 Å. There are three inequivalent Rh sites. In the first Rh site, Rh is bonded in a 6-coordinate geometry to six Hf atoms. In the second Rh site, Rh is bonded in a 5-coordinate geometry to five Hf atoms. In the third Rh site, Rh is bonded in a 6-coordinate geometry to six Hf atoms.

36 MATERIALS SCIENCE↗

Materials Data on Ti3Rh5 by Materials Project

Ti3Rh5 crystallizes in the orthorhombic Pbam space group. The structure is three-dimensional. there are two inequivalent Ti sites. In the first Ti site, Ti is bonded in a body-centered cubic geometry to eight Rh atoms. There are a spread of Ti–Rh bond distances ranging from 2.55–2.71 Å. In the second Ti site, Ti is bonded in a 10-coordinate geometry to ten Rh atoms. There are a spread of Ti–Rh bond distances ranging from 2.60–2.88 Å. There are three inequivalent Rh sites. In the first Rh site, Rh is bonded in a 6-coordinate geometry to six Ti atoms. In the second Rh site, Rh is bonded in a 5-coordinate geometry to five Ti atoms. In the third Rh site, Rh is bonded in a 6-coordinate geometry to six Ti atoms.

36 MATERIALS SCIENCE↗

Materials Data on Yb(As2Rh3)2 by Materials Project

Yb(Rh3As2)2 crystallizes in the hexagonal P-6m2 space group. The structure is three-dimensional. Yb is bonded to six equivalent Rh and six equivalent As atoms to form face-sharing YbAs6Rh6 cuboctahedra. All Yb–Rh bond lengths are 3.15 Å. All Yb–As bond lengths are 3.05 Å. There are two inequivalent Rh sites. In the first Rh site, Rh is bonded in a 5-coordinate geometry to five As atoms. There are one shorter (2.55 Å) and four longer (2.59 Å) Rh–As bond lengths. In the second Rh site, Rh is bonded in a 6-coordinate geometry to two equivalent Yb and four As atoms. There are two shorter (2.45 Å) and two longer (2.55 Å) Rh–As bond lengths. There are two inequivalent As sites. In the first As site, As is bonded in a 8-coordinate geometry to two equivalent Yb and six Rh atoms. In the second As site, As is bonded in a 9-coordinate geometry to nine Rh atoms.

36 MATERIALS SCIENCE↗

Materials Data on Tm5(Ge5Rh2)2 by Materials Project

Tm5Rh4Ge10 crystallizes in the tetragonal P4/mbm space group. The structure is three-dimensional. there are three inequivalent Tm sites. In the first Tm site, Tm is bonded in a 12-coordinate geometry to four equivalent Rh and ten Ge atoms. All Tm–Rh bond lengths are 3.31 Å. There are a spread of Tm–Ge bond distances ranging from 3.23–3.36 Å. In the second Tm site, Tm is bonded to four equivalent Rh and eight Ge atoms to form face-sharing TmGe8Rh4 cuboctahedra. All Tm–Rh bond lengths are 3.10 Å. There are a spread of Tm–Ge bond distances ranging from 2.90–3.12 Å. In the third Tm site, Tm is bonded in a 8-coordinate geometry to four equivalent Rh and twelve Ge atoms. All Tm–Rh bond lengths are 3.21 Å. There are eight shorter (2.95 Å) and four longer (3.35 Å) Tm–Ge bond lengths. Rh is bonded in a 5-coordinate geometry to five Tm and five Ge atoms. There are a spread of Rh–Ge bond distances ranging from 2.44–2.57 Å. There are three inequivalent Ge sites. In the first Ge site, Ge is bonded in a 2-coordinate geometry to four Tm, two equivalent Rh, and two equivalent Ge atoms. Both Ge–Ge bond lengths are 2.88 Å. In the second Ge site, Ge is bonded in a 2-coordinate geometry to five Tm, two equivalent Rh, and one Ge atom. The Ge–Ge bond length is 2.53 Å. In the third Ge site, Ge is bonded in a 9-coordinate geometry to six Tm, two equivalent Rh, and one Ge atom. The Ge–Ge bond length is 2.46 Å.

36 MATERIALS SCIENCE↗

Materials Data on Ho5(Ge5Rh2)2 by Materials Project

Ho5(Rh2Ge5)2 crystallizes in the tetragonal P4/mbm space group. The structure is three-dimensional. there are three inequivalent Ho sites. In the first Ho site, Ho is bonded in a 8-coordinate geometry to four equivalent Rh and twelve Ge atoms. All Ho–Rh bond lengths are 3.22 Å. There are eight shorter (2.98 Å) and four longer (3.36 Å) Ho–Ge bond lengths. In the second Ho site, Ho is bonded in a 12-coordinate geometry to four equivalent Rh and ten Ge atoms. All Ho–Rh bond lengths are 3.33 Å. There are a spread of Ho–Ge bond distances ranging from 3.24–3.35 Å. In the third Ho site, Ho is bonded to four equivalent Rh and eight Ge atoms to form face-sharing HoGe8Rh4 cuboctahedra. All Ho–Rh bond lengths are 3.12 Å. There are a spread of Ho–Ge bond distances ranging from 2.93–3.14 Å. Rh is bonded in a 5-coordinate geometry to five Ho and five Ge atoms. There are a spread of Rh–Ge bond distances ranging from 2.45–2.58 Å. There are three inequivalent Ge sites. In the first Ge site, Ge is bonded in a 9-coordinate geometry to six Ho, two equivalent Rh, and one Ge atom. The Ge–Ge bond length is 2.47 Å. In the second Ge site, Ge is bonded in a 2-coordinate geometry to five Ho, two equivalent Rh, and one Ge atom. The Ge–Ge bond length is 2.54 Å. In the third Ge site, Ge is bonded in a 2-coordinate geometry to four Ho and two equivalent Rh atoms.

36 MATERIALS SCIENCE↗

Materials Data on Zr3Rh5 by Materials Project

Zr3Rh5 crystallizes in the orthorhombic Cmcm space group. The structure is three-dimensional. there are two inequivalent Zr sites. In the first Zr site, Zr is bonded in a 9-coordinate geometry to nine Rh atoms. There are a spread of Zr–Rh bond distances ranging from 2.63–2.99 Å. In the second Zr site, Zr is bonded in a 10-coordinate geometry to ten Rh atoms. There are a spread of Zr–Rh bond distances ranging from 2.75–2.98 Å. There are three inequivalent Rh sites. In the first Rh site, Rh is bonded in a 6-coordinate geometry to six Zr atoms. In the second Rh site, Rh is bonded in a 6-coordinate geometry to six Zr atoms. In the third Rh site, Rh is bonded in a 5-coordinate geometry to five Zr atoms.

36 MATERIALS SCIENCE↗

Materials Data on Mg5Rh2 by Materials Project

Mg5Rh2 crystallizes in the hexagonal P6_3/mmc space group. The structure is three-dimensional. there are three inequivalent Mg sites. In the first Mg site, Mg is bonded in a 12-coordinate geometry to six equivalent Rh atoms. All Mg–Rh bond lengths are 2.72 Å. In the second Mg site, Mg is bonded in a 3-coordinate geometry to three Rh atoms. There are two shorter (2.75 Å) and one longer (3.08 Å) Mg–Rh bond lengths. In the third Mg site, Mg is bonded in a 2-coordinate geometry to four Rh atoms. There are a spread of Mg–Rh bond distances ranging from 2.60–2.93 Å. There are two inequivalent Rh sites. In the first Rh site, Rh is bonded in a 6-coordinate geometry to nine Mg atoms. In the second Rh site, Rh is bonded in a 10-coordinate geometry to ten Mg atoms.

36 MATERIALS SCIENCE↗

Materials Data on Rh3Se8 by Materials Project

Rh3Se8 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. there are two inequivalent Rh+3.33+ sites. In the first Rh+3.33+ site, Rh+3.33+ is bonded to six Se+1.25- atoms to form RhSe6 octahedra that share corners with eight RhSe6 octahedra and corners with two equivalent SeRh3Se tetrahedra. The corner-sharing octahedra tilt angles range from 63–66°. There are a spread of Rh–Se bond distances ranging from 2.49–2.57 Å. In the second Rh+3.33+ site, Rh+3.33+ is bonded to six Se+1.25- atoms to form corner-sharing RhSe6 octahedra. The corner-sharing octahedra tilt angles range from 63–66°. There are a spread of Rh–Se bond distances ranging from 2.52–2.54 Å. There are four inequivalent Se+1.25- sites. In the first Se+1.25- site, Se+1.25- is bonded to three Rh+3.33+ and one Se+1.25- atom to form distorted SeRh3Se tetrahedra that share corners with two equivalent RhSe6 octahedra and corners with three equivalent SeRh3Se tetrahedra. The corner-sharing octahedra tilt angles range from 79–80°. The Se–Se bond length is 2.46 Å. In the second Se+1.25- site, Se+1.25- is bonded in a 2-coordinate geometry to two equivalent Rh+3.33+ and one Se+1.25- atom. In the third Se+1.25- site, Se+1.25- is bonded in a 3-coordinate geometry to two Rh+3.33+ and one Se+1.25- atom. The Se–Se bond length is 2.44 Å. In the fourth Se+1.25- site, Se+1.25- is bonded in a 3-coordinate geometry to two Rh+3.33+ and one Se+1.25- atom. The Se–Se bond length is 2.45 Å.

36 MATERIALS SCIENCE↗

Materials Data on Ce(PRh)2 by Materials Project

Ce(RhP)2 crystallizes in the tetragonal P4/nmm space group. The structure is three-dimensional. Ce is bonded in a 12-coordinate geometry to eight Rh and eight P atoms. There are four shorter (3.19 Å) and four longer (3.21 Å) Ce–Rh bond lengths. There are four shorter (3.12 Å) and four longer (3.15 Å) Ce–P bond lengths. There are two inequivalent Rh sites. In the first Rh site, Rh is bonded in a 9-coordinate geometry to four equivalent Ce and five P atoms. There are four shorter (2.35 Å) and one longer (2.36 Å) Rh–P bond lengths. In the second Rh site, Rh is bonded in a 12-coordinate geometry to four equivalent Ce and four equivalent P atoms. All Rh–P bond lengths are 2.47 Å. There are two inequivalent P sites. In the first P site, P is bonded in a 8-coordinate geometry to four equivalent Ce and four equivalent Rh atoms. In the second P site, P is bonded in a 9-coordinate geometry to four equivalent Ce and five Rh atoms.

36 MATERIALS SCIENCE↗