Er

Traditional Materials TRA Elasticity Data ELA

MP-ID: mp-99 · Space group: P6_3/mmc (#194)

Materials Project API

Basic Information

Formula

MP-ID

mp-99

Elements

Sites

Density

9.0448

g/cm³

Volume

61.41

Å³

Cell a

3.5885

Cell b

3.5885

Cell c

5.5070

α Angle

90.00

β Angle

90.00

γ Angle

120.00

Space Group

P6_3/mmc

Point Group

6/mmm

Crystal System

Hexagonal

Bravais Lattice

Stability

Packing Fraction

0.7405

X-ray Diffraction

Diffraction Pattern

Target / Radiation

X-axis: 2θ (°); Y-axis: relative intensity; Cu Kα ; λ=1.5418 Å

Diffraction Peaks (Top 22)

2θ	d (Å)	I	hkl
28.73	3.1077	24.1	(1,0,-1,0)
32.52	2.7535	23.3	(0,0,0,2)
33.10	2.7065	100.0	(1,0,-1,1)
43.93	2.0609	15.3	(1,0,-1,2)
50.89	1.7943	20.0	(2,-1,-1,0)
58.39	1.5805	19.9	(1,0,-1,3)
59.49	1.5539	1.0	(2,0,-2,0)
59.49	1.5539	2.1	(2,-2,0,0)
61.71	1.5033	15.0	(2,-1,-1,2)
61.71	1.5033	7.5	(1,-2,1,2)
62.06	1.4955	16.6	(2,0,-2,1)
68.11	1.3767	2.8	(0,0,0,4)
69.46	1.3533	1.3	(2,0,-2,2)
69.46	1.3533	2.6	(2,-2,0,2)
75.53	1.2588	3.1	(1,0,-1,4)
81.09	1.1860	5.2	(2,0,-2,3)
81.09	1.1860	2.6	(2,-2,0,3)
82.04	1.1746	1.3	(3,-1,-2,0)
84.30	1.1488	2.4	(2,1,-3,1)
84.30	1.1488	7.1	(3,-1,-2,1)
84.30	1.1488	4.8	(2,-3,1,1)
89.79	1.0923	8.4	(2,-1,-1,4)

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Energy Properties

Formation Energy/atom

0.01244

eV/atom

Energy/atom

-33.91299

eV/atom

Energy above Hull

0.0124

eV/atom

Uncorrected Energy

-33.9130

eV/atom

Volume/atom

30.71

Å³

c/a Ratio

1.5346

Electronic Properties

Metallic

Metal

Band Gap

Direct Gap

CBM

N/A

Magnetic Properties

Magnetic

Yes

Total Mag. Moment

0.0000

μB

Mag. Ordering

Unknown

Mag. Sites

Magnetization/Volume

0.000000

μB/Å³

Elastic Properties

K_VRH

44.760

GPa

G_VRH

31.020

GPa

Young's Modulus E

75.596

GPa

Poisson Ratio ν

0.219

Pugh Ratio K/G

1.443

Vickers Hardness Est.

6.712

GPa

Ductility

Ductile

Anisotropy

0.013

Lame λ

24.080

GPa

Feature Analysis

Composition Overview

Element Composition (atomic fraction)

Composition Info

Major / Matrix Element

Er · 1.000

Element Family

N/A

Solute Fraction

0.000

Interstitial Fraction

0.000

Traditional Material Features

ROM Blended-Feature Radar

Rating & Classification

Tier

Score

0.565

Family

Pure Metal

Matrix Element

Er · 1.000

Elasticity Features

Elastic Modulus Comparison (GPa)

Elastic Features

Elastic Anisotropy A^U

0.0130

Homogeneous Poisson ν

0.2190

Homogeneity

0.2190

Related Tasks

Related computation task IDs (5)

aaadmpkg aaadqynv aaaegrho aaaeupin aaafcbdp

Citation & References

Materials Project Page

https://materialsproject.org/materials/mp-99

Reference Citation

The crystal structure and related material properties of Er were obtained from the Materials Project database (MP-ID: mp-99, database version v2026.04.13).

Literature Citation

Horton, M.K., Huck, P., Yang, R.X. et al. Accelerated data-driven materials science with the Materials Project. Nat. Mater. 24, 1522–1532 (2025). https://doi.org/10.1038/s41563-025-02272-0

3D Crystal Structure Rendering

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Raw CIF Data

# generated using pymatgen
data_Er
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.58849678
_cell_length_b   3.58849640
_cell_length_c   5.50697138
_cell_angle_alpha   90.00000000
_cell_angle_beta   90.00000000
_cell_angle_gamma   119.99999371
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Er
_chemical_formula_sum   Er2
_cell_volume   61.41416550
_cell_formula_units_Z   2
loop_
 _symmetry_equiv_pos_site_id
 _symmetry_equiv_pos_as_xyz
  1  'x, y, z'
loop_
 _atom_site_type_symbol
 _atom_site_label
 _atom_site_symmetry_multiplicity
 _atom_site_fract_x
 _atom_site_fract_y
 _atom_site_fract_z
 _atom_site_occupancy
  Er  Er0  1  0.33333300  0.66666700  0.25000000  1.0
  Er  Er1  1  0.66666700  0.33333300  0.75000000  1.0

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