moftransformer 2.1.3

moftransformer

PMTransformer (MOFTransformer)

This package provides a universal transfer learning model, PMTransformer (Porous Materials Transformer), which obtains the state-of-the-art performance in predicting various properties of porous materials. The PMTRansformer was pre-trainied with 1.9 million hypothetical porous materials including Metal-Organic Frameworks (MOFs), Covalent-Organic Frameworks (COFs), Porous Polymer Networks (PPNs), and zeolites. By fine-tuning the pre-trained PMTransformer, you can easily obtain machine learning models to accurately predict various properties of porous materials .

NOTE: From version 2.0.0, the default pre-training model has been changed from MOFTransformer to PMTransformer, which was pre-trained with a larger dataset, containing other porous materials as well as MOFs. The PMTransformer outperforms the MOFTransformer in predicting various properties of porous materials.

Install

Depedencies

NOTE: This package is primarily tested on Linux. We strongly recommend using Linux for the installation.

python>=3.8

Given that MOFTransformer is based on pytorch, please install pytorch (>= 1.12.0) according to your environments.

Installation using PIP

$ pip install moftransformer

Download the pretrained models (ckpt file)

• you can download the pretrained models (PMTransformer.ckpt and MOFTransformer.ckpt) via figshare

or you can download with a command line:

$ moftransformer download pretrain_model

(Optional) Download pre-embeddings for CoREMOF, QMOF

• we've provide the pre-embeddings (i.e., atom-based graph embeddings and energy-grid embeddings), inputs of PMTransformer, for CoREMOF, QMOF database.

$ moftransformer download coremof
$ moftransformer download qmof

Getting Started

1. At first, you download dataset of hMOFs (20,000 MOFs) as an example.

$ moftransformer download hmof

2. Fine-tune the pretrained MOFTransformer.

import moftransformer
from moftransformer.examples import example_path

# data root and downstream from example
root_dataset = example_path['root_dataset']
downstream = example_path['downstream']
log_dir = './logs/'
# load_path = "pmtransformer" (default)

# kwargs (optional)
max_epochs = 10
batch_size = 8
mean = 0
std = 1


moftransformer.run(root_dataset, downstream, log_dir=log_dir,                   
                   max_epochs=max_epochs, batch_size=batch_size,
                   mean=mean, std=std)

3. Test fine-tuned model

from pathlib import Path
import moftransformer
from moftransformer.examples import example_path

root_dataset = example_path['root_dataset']
downstream = example_path['downstream']

# Get ckpt file
seed = 0               # default seeds
version = 0            # version for model. It increases with the number of trains

# For version > 2.1.1, best.ckpt exists
checkpoint = 'best'    # Epochs where the model is stored. 
save_dir = 'result/'

# optional keyword
mean = 0
std = 1

load_path = Path(log_dir) / f'pretrained_mof_seed{seed}_from_pmtransformer/version_{version}/checkpoints/{checkpoint}.ckpt'

if not load_path.exists():
    raise ValueError(f'load_path does not exists. check path for .ckpt file : {load_path}')

moftransformer.test(root_dataset, load_path, downstream=downstream,
                   save_dir=save_dir, mean=mean, std=std)

4. predict from fine-tuned model

from pathlib import Path
import moftransformer
from moftransformer.examples import example_path

root_dataset = example_path['root_dataset']
downstream = example_path['downstream']

# Get ckpt file
log_dir = './logs/'    # same directory make from training
seed = 0               # default seeds
version = 0            # version for model. It increases with the number of trains
checkpoint = 'best'    # Epochs where the model is stored. 
mean = 0
std = 1

load_path = Path(log_dir) / f'pretrained_mof_seed{seed}_from_pmtransformer/version_{version}/checkpoints/{checkpoint}.ckpt'

if not load_path.exists():
    raise ValueError(f'load_path does not exists. check path for .ckpt file : {load_path}')
    
moftransformer.predict(
    root_dataset, load_path=load_path, downstream=downstream, split='all', mean=mean, std=std
)

5. Visualize analysis of feature importance for the fine-tuned model.

%matplotlib widget
from visualize import PatchVisualizer

model_path = "examples/finetuned_bandgap.ckpt" # or 'examples/finetuned_h2_uptake.ckpt'
data_path = 'examples/visualize/dataset/'
cifname = 'MIBQAR01_FSR'

vis = PatchVisualizer.from_cifname(cifname, model_path, data_path)
vis.draw_graph() # or vis.draw_grid()

Architecture

It is a multi-modal pre-training Transformer encoder which is designed to capture both local and global features of porous materials.

The pre-traning tasks are as follows: (1) Topology Prediction (2) Void Fraction Prediction (3) Building Block Classification

It takes two different representations as input

• Atom-based Graph Embedding : CGCNN w/o pooling layer -> local features
• Energy-grid Embedding : 1D flatten patches of 3D energy grid -> global features

Feature Importance Anaylsis

you can easily visualize feature importance analysis of atom-based graph embeddings and energy-grid embeddings.

%matplotlib widget
from visualize import PatchVisualizer

model_path = "examples/finetuned_bandgap.ckpt" # or 'examples/finetuned_h2_uptake.ckpt'
data_path = 'examples/visualize/dataset/'
cifname = 'MIBQAR01_FSR'

vis = PatchVisualizer.from_cifname(cifname, model_path, data_path)
vis.draw_graph()

vis = PatchVisualizer.from_cifname(cifname, model_path, data_path)
vis.draw_grid()

Universal Transfer Learning

Comparison of mean absolute error (MAE) values for various baseline models, scratch, MOFTransformer, and PMTransformer on different properties of MOFs, COFs, PPNs, and zeolites. The bold values indicate the lowest MAE value for each property. The details of information can be found in PMTransformer paper

Material	Property	Number of Dataset	Energy histogram	Descriptor-based ML	CGCNN	Scratch	MOFTransformer	PMTransformer
MOF	H2 Uptake (100 bar)	20,000	9.183	9.456	32.864	7.018	6.377	5.963
MOF	H2 diffusivity (dilute)	20,000	0.644	0.398	0.6600	0.391	0.367	0.366
MOF	Band-gap	20.373	0.913	0.590	0.290	0.271	0.224	0.216
MOF	N2 uptake (1 bar)	5,286	0.178	0.115	0.108	0.102	0.071	0.069
MOF	O2 uptake (1 bar)	5,286	0.162	0.076	0.083	0.071	0.051	0.053
MOF	N2 diffusivity (1 bar)	5,286	7.82e-5	5.22e-5	7.19e-5	5.82e-05	4.52e-05	4.53e-05
MOF	O2 diffusivity (1 bar)	5,286	7.14e-5	4.59e-5	6.56e-5	5.00e-05	4.04e-05	3.99e-05
MOF	CO2 Henry coefficient	8,183	0.737	0.468	0.426	0.362	0.295	0.288
MOF	Thermal stability	3,098	68.74	49.27	52.38	52.557	45.875	45.766
COF	CH4 uptake (65bar)	39,304	5.588	4.630	15.31	2.883	2.268	2.126
COF	CH4 uptake (5.8bar)	39,304	3.444	1.853	5.620	1.255	0.999	1.009
COF	CO2 heat of adsorption	39,304	2.101	1.341	1.846	1.058	0.874	0.842
COF	CO2 log KH	39,304	0.242	0.169	0.238	0.134	0.108	0.103
PPN	CH4 uptake (65bar)	17,870	6.260	4.233	9.731	3.748	3.187	2.995
PPN	CH4 uptake (1bar)	17,870	1.356	0.563	1.525	0.602	0.493	0.461
Zeolite	CH4 KH (unitless)	99,204	8.032	6.268	6.334	4.286	4.103	3.998
Zeolite	CH4 Heat of adsorption	99,204	1.612	1.033	1.603	0.670	0.647	0.639

Citation

if you want to cite PMTransformer or MOFTransformer, please refer to the following paper:

1. A multi-modal pre-training transformer for universal transfer learning in metal–organic frameworks, Nature Machine Intelligence, 5, 2023. link

2. PMTransformer: Universal Transfer Learning and Cross-material Few-shot Learning in Porous Materials, (submitted). link

Contributing 🙌

Contributions are welcome! If you have any suggestions or find any issues, please open an issue or a pull request.

License 📄

This project is licensed under the MIT License. See the LICENSE file for more information.