đ ChemVLM-8B: A Multimodal Large Language Model for Chemistry
ChemVLM-8B is an 8-billion parameter multimodal large language model tailored for chemical applications, offering enhanced capabilities in processing chemical visual and textual information.
đ Quick Start
Prerequisites
Install the required libraries using the following command:
pip install transformers>=4.37.0 sentencepiece einops timm accelerate>=0.26.0
Ensure that torch
and torchvision
are also installed.
Code Example
from transformers import AutoTokenizer, AutoModelforCasualLM
import torch
import torchvision.transforms as T
import transformers
from torchvision.transforms.functional import InterpolationMode
IMAGENET_MEAN = (0.485, 0.456, 0.406)
IMAGENET_STD = (0.229, 0.224, 0.225)
IMAGENET_MEAN = (0.485, 0.456, 0.406)
IMAGENET_STD = (0.229, 0.224, 0.225)
def build_transform(input_size):
MEAN, STD = IMAGENET_MEAN, IMAGENET_STD
transform = T.Compose([
T.Lambda(lambda img: img.convert('RGB') if img.mode != 'RGB' else img),
T.Resize((input_size, input_size), interpolation=InterpolationMode.BICUBIC),
T.ToTensor(),
T.Normalize(mean=MEAN, std=STD)
])
return transform
def find_closest_aspect_ratio(aspect_ratio, target_ratios, width, height, image_size):
best_ratio_diff = float('inf')
best_ratio = (1, 1)
area = width * height
for ratio in target_ratios:
target_aspect_ratio = ratio[0] / ratio[1]
ratio_diff = abs(aspect_ratio - target_aspect_ratio)
if ratio_diff < best_ratio_diff:
best_ratio_diff = ratio_diff
best_ratio = ratio
elif ratio_diff == best_ratio_diff:
if area > 0.5 * image_size * image_size * ratio[0] * ratio[1]:
best_ratio = ratio
return best_ratio
def dynamic_preprocess(image, min_num=1, max_num=6, image_size=448, use_thumbnail=False):
orig_width, orig_height = image.size
aspect_ratio = orig_width / orig_height
target_ratios = set(
(i, j) for n in range(min_num, max_num + 1) for i in range(1, n + 1) for j in range(1, n + 1) if
i * j <= max_num and i * j >= min_num)
target_ratios = sorted(target_ratios, key=lambda x: x[0] * x[1])
target_aspect_ratio = find_closest_aspect_ratio(
aspect_ratio, target_ratios, orig_width, orig_height, image_size)
target_width = image_size * target_aspect_ratio[0]
target_height = image_size * target_aspect_ratio[1]
blocks = target_aspect_ratio[0] * target_aspect_ratio[1]
resized_img = image.resize((target_width, target_height))
processed_images = []
for i in range(blocks):
box = (
(i % (target_width // image_size)) * image_size,
(i // (target_width // image_size)) * image_size,
((i % (target_width // image_size)) + 1) * image_size,
((i // (target_width // image_size)) + 1) * image_size
)
split_img = resized_img.crop(box)
processed_images.append(split_img)
assert len(processed_images) == blocks
if use_thumbnail and len(processed_images) != 1:
thumbnail_img = image.resize((image_size, image_size))
processed_images.append(thumbnail_img)
return processed_images
def load_image(image_file, input_size=448, max_num=6):
image = Image.open(image_file).convert('RGB')
transform = build_transform(input_size=input_size)
images = dynamic_preprocess(image, image_size=input_size, use_thumbnail=True, max_num=max_num)
pixel_values = [transform(image) for image in images]
pixel_values = torch.stack(pixel_values)
return pixel_values
tokenizer = AutoTokenizer.from_pretrained('AI4Chem/ChemVLM-8B', trust_remote_code=True)
model = AutoModelForCausalLM.from_pretrained(
"AI4Chem/ChemVLM-8B",
torch_dtype=torch.bfloat16,
low_cpu_mem_usage=True,
trust_remote_code=True
).cuda().eval()
query = "Please describe the molecule in the image."
image_path = "your image path"
pixel_values = load_image(image_path, max_num=6).to(torch.bfloat16).cuda()
gen_kwargs = {"max_length": 1000, "do_sample": True, "temperature": 0.7, "top_p": 0.9}
response = model.chat(tokenizer, pixel_values, query, gen_kwargs)
print(response)
⨠Features
- Multimodal Capability: ChemVLM-8B can handle both visual and textual chemical information, such as molecular structures, reactions, and chemistry exam questions.
- Bilingual Training: Trained on a bilingual multimodal dataset, enhancing its cross - language understanding in the chemical domain.
- Competitive Performance: Achieves competitive results on various chemical tasks compared to other open - source and proprietary multimodal large language models.
đ Documentation
Paper
ChemVLM: Exploring the Power of Multimodal Large Language Models in Chemistry Area
Abstract
Large Language Models (LLMs) have achieved remarkable success and have been applied across various scientific fields, including chemistry. However, many chemical tasks require the processing of visual information, which cannot be successfully handled by existing chemical LLMs. This brings a growing need for models capable of integrating multimodal information in the chemical domain. In this paper, we introduce ChemVLM, an open - source chemical multimodal large language model specifically designed for chemical applications. ChemVLM is trained on a carefully curated bilingual multimodal dataset that enhances its ability to understand both textual and visual chemical information, including molecular structures, reactions, and chemistry examination questions. We develop three datasets for comprehensive evaluation, tailored to Chemical Optical Character Recognition (OCR), Multimodal Chemical Reasoning (MMCR), and Multimodal Molecule Understanding tasks. We benchmark ChemVLM against a range of open - source and proprietary multimodal large language models on various tasks. Experimental results demonstrate that ChemVLM achieves competitive performance across all evaluated tasks. Our model can be found at https://huggingface.co/AI4Chem/ChemVLM - 26B.
Model Description
The architecture of ChemVLM is based on InternVLM and incorporates both vision and language processing components. The model is trained on a bilingual multimodal dataset containing chemical information, including molecular structures, reactions, and chemistry exam questions. More details about the architecture can be found in the Github README.

đ§ Technical Details
The architecture of ChemVLM-8B is built upon InternVLM, integrating vision and language processing modules. It is trained on a bilingual multimodal dataset rich in chemical information, enabling it to understand and process various chemical data types.
đ License
The model is released under the apache - 2.0 license.
đĻ Installation
Install the necessary libraries using the following command:
pip install transformers>=4.37.0 sentencepiece einops timm accelerate>=0.26.0
Ensure that torch
and torchvision
are also installed.
đ Performances of our 8b model on several tasks
Datasets |
MMChemOCR |
CMMU |
MMCR - bench |
Reaction type |
Metrics |
tanimoto similarity\tani@1.0 |
score(%, GPT - 4o helps judge) |
score(%, GPT - 4o helps judge) |
Accuracy(%) |
Scores of ChemVLM - 8b |
81.75/57.69 |
52.7(SOTA) |
33.6 |
16.79 |
đ Citation
@inproceedings{li2025chemvlm,
title={Chemvlm: Exploring the power of multimodal large language models in chemistry area},
author={Li, Junxian and Zhang, Di and Wang, Xunzhi and Hao, Zeying and Lei, Jingdi and Tan, Qian and Zhou, Cai and Liu, Wei and Yang, Yaotian and Xiong, Xinrui and others},
booktitle={Proceedings of the AAAI Conference on Artificial Intelligence},
volume={39},
number={1},
pages={415--423},
year={2025}
}
đģ Codebase and Datasets
The codebase and datasets can be found at https://github.com/AI4Chem/ChemVlm.